dateutil 2.6 gives segfault in normalizing timestamp with datetutil timezone
Newly release dateutil 2.6.0 breaks some of the tests related to the use of dateutil timezones (travis is therefore currently failing)

---

Original report:

#### A small, complete example of the issue
I maintain central installs of miniconda environments that include pandas. My previous environment with pandas 0.19.0,  if I did this 
```python
python -c "import pandas; pandas.test('fast')"
```
it worked. Now with pandas 0.19.1, it seg faults. Other packages may have been updated in the new environment. 

Below are details - first the failure in my ana-1.0.5 environment, it is clearly segfaulting on a test maybe 2/3 the way through? Then the success in my ana-1.0.4 environment, then the pd.get_versions() in the working old environment, and finally in the newer environment where it fails:

<details>
```
(ana-1.0.5) pslogin7a: ~/rel/slaclab_conda/anarel-test $ python -c "import pandas; pandas.test('fast')"
Running unit tests for pandas
pandas version 0.19.1
numpy version 1.11.2
pandas is installed in /reg/g/psdm/sw/conda/inst/miniconda2-dev-rhel7/envs/ana-1.0.5/lib/python2.7/site-packages/pandas
Python version 2.7.12 |Continuum Analytics, Inc.| (default, Jul  2 2016, 17:42:40) [GCC 4.4.7 20120313 (Red Hat 4.4.7-1)]
nose version 1.3.7
/reg/g/psdm/sw/conda/inst/miniconda2-dev-rhel7/envs/ana-1.0.5/lib/python2.7/site-packages/nose/importer.py:94: FutureWarning: The pandas.rpy module is deprecated and will be removed in a future version. We refer to external packages like rpy2. 
See here for a guide on how to port your code to rpy2: http://pandas.pydata.org/pandas-docs/stable/r_interface.html
  mod = load_module(part_fqname, fh, filename, desc)
...................................................................................S...........................S.......S.......S.......S.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................S............SS.....................................................................................................................................................................................................S............SS...S................................................................................................................................................................................S............SS..S...............S...................................S.........S.SSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS.SSSSS.S........SS...SS.SS.....................................................................................................................S.......................S......................................................................SSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS..SS..................................................S.............................................................................................................................................................................................................................................................................................................................................................S................................................................................S..SS.....SSSSSSSSSSSSSSSSSSSSSSSSSSS....................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................S..S...............................................................Segmentation fault (core dumped)
(ana-1.0.5) pslogin7a: ~/rel/slaclab_conda/anarel-test $ (ana-1.0.5) pslogin7a: ~/rel/slaclab_conda/anarel-test $ python -c "import pandas; pandas.test('fast')"
-bash: syntax error near unexpected token `pslogin7a:'
(ana-1.0.5) pslogin7a: ~/rel/slaclab_conda/anarel-test $ Running unit tests for pandas
-bash: Running: command not found
(ana-1.0.5) pslogin7a: ~/rel/slaclab_conda/anarel-test $ pandas version 0.19.1
-bash: pandas: command not found
(ana-1.0.5) pslogin7a: ~/rel/slaclab_conda/anarel-test $ numpy version 1.11.2
-bash: numpy: command not found
(ana-1.0.5) pslogin7a: ~/rel/slaclab_conda/anarel-test $ pandas is installed in /reg/g/psdm/sw/conda/inst/miniconda2-dev-rhel7/envs/ana-1.0.5/lib/python2.7/site-packages/pandas
-bash: pandas: command not found
(ana-1.0.5) pslogin7a: ~/rel/slaclab_conda/anarel-test $ Python version 2.7.12 |Continuum Analytics, Inc.| (default, Jul  2 2016, 17:42:40) [GCC 4.4.7 20120313 (Red Hat 4.4.7-1)]
-bash: syntax error near unexpected token `[GCC'
(ana-1.0.5) pslogin7a: ~/rel/slaclab_conda/anarel-test $ nose version 1.3.7
-bash: nose: command not found
(ana-1.0.5) pslogin7a: ~/rel/slaclab_conda/anarel-test $ source activate ana-1.0.4
(ana-1.0.4) pslogin7a: ~/rel/slaclab_conda/anarel-test $ python -c "import pandas; pandas.test('fast')"
Running unit tests for pandas
pandas version 0.19.0
numpy version 1.11.2
pandas is installed in /reg/g/psdm/sw/conda/inst/miniconda2-dev-rhel7/envs/ana-1.0.4/lib/python2.7/site-packages/pandas
Python version 2.7.12 |Continuum Analytics, Inc.| (default, Jul  2 2016, 17:42:40) [GCC 4.4.7 20120313 (Red Hat 4.4.7-1)]
nose version 1.3.7
/reg/g/psdm/sw/conda/inst/miniconda2-dev-rhel7/envs/ana-1.0.4/lib/python2.7/site-packages/nose/importer.py:94: FutureWarning: The pandas.rpy module is deprecated and will be removed in a future version. We refer to external packages like rpy2. 
See here for a guide on how to port your code to rpy2: http://pandas.pydata.org/pandas-docs/stable/r_interface.html
  mod = load_module(part_fqname, fh, filename, desc)
..............................................................................................................S.......S.......S.......S..................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................S............SS..................................................................................................................................................................................................S............SS...S.............................................................................................................................................................................S............SS..S...............S...................................S.........S.SSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS.SSSSS.S........SS...SS.SS.....................................................................................................................S.......................S......................................................................SSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS..SS..................................................S.............................................................................................................................................................................................................................................................................................................................................................S................................................................................S..SS.....SSSSSSSSSSSSSSSSSSSSSSSSSSS..................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................S..S.......................................................................................................................................................................................................S..............................................................S...S..............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................S....................................................................................................................................................................................................................................................................................................................SSS.......................................................................................................................................................................................................S.......................................................................................................................................................................................................................................................................................................................................................................................................................................................................................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----------------------------------------------------------------------
Ran 10625 tests in 701.643s

OK (SKIP=537)
(ana-1.0.4) pslogin7a: ~/rel/slaclab_conda/anarel-test $ python -c "import pandas; pandas.show_versions()"

INSTALLED VERSIONS
------------------
commit: None
python: 2.7.12.final.0
python-bits: 64
OS: Linux
OS-release: 3.10.0-327.13.1.el7.x86_64
machine: x86_64
processor: x86_64
byteorder: little
LC_ALL: None
LANG: C
LOCALE: None.None

pandas: 0.19.0
nose: 1.3.7
pip: 8.1.2
setuptools: 27.2.0
Cython: 0.24.1
numpy: 1.11.2
scipy: 0.18.1
statsmodels: None
xarray: 0.8.2
IPython: 5.1.0
sphinx: 1.4.8
patsy: None
dateutil: 2.5.3
pytz: 2016.7
blosc: None
bottleneck: 1.1.0
tables: 3.3.0
numexpr: 2.6.1
matplotlib: 1.5.1
openpyxl: None
xlrd: None
xlwt: None
xlsxwriter: None
lxml: None
bs4: None
html5lib: None
httplib2: None
apiclient: None
sqlalchemy: None
pymysql: None
psycopg2: None
jinja2: 2.8
boto: None
pandas_datareader: None
(ana-1.0.4) pslogin7a: ~/rel/slaclab_conda/anarel-test $ source activate ana-1.0.5
(ana-1.0.5) pslogin7a: ~/rel/slaclab_conda/anarel-test $ python -c "import pandas; pandas.show_versions()"

INSTALLED VERSIONS
------------------
commit: None
python: 2.7.12.final.0
python-bits: 64
OS: Linux
OS-release: 3.10.0-327.13.1.el7.x86_64
machine: x86_64
processor: x86_64
byteorder: little
LC_ALL: None
LANG: C
LOCALE: None.None

pandas: 0.19.1
nose: 1.3.7
pip: 9.0.1
setuptools: 27.2.0
Cython: 0.25.1
numpy: 1.11.2
scipy: 0.18.1
statsmodels: None
xarray: 0.8.2
IPython: 5.1.0
sphinx: 1.4.8
patsy: None
dateutil: 2.6.0
pytz: 2016.7
blosc: None
bottleneck: 1.1.0
tables: 3.3.0
numexpr: 2.6.1
matplotlib: 1.5.1
openpyxl: None
xlrd: None
xlwt: None
xlsxwriter: None
lxml: None
bs4: None
html5lib: None
httplib2: None
apiclient: None
sqlalchemy: None
pymysql: None
psycopg2: None
jinja2: 2.8
boto: None
pandas_datareader: None
(ana-1.0.5) pslogin7a: ~/rel/slaclab_conda/anarel-test $ 
```
</details>