New attribute error associated with tseries
Hi Wes,

After having gotten pandas to build and run on 10.7 previously, an updated build based on the current Github source yields the following AttributeError, also related to _tseries (which appears to be "lib" in this case):

```
In [1]: from pandas import *
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
/Users/fonnescj/<ipython-input-1-7463a510993d> in <module>()
----> 1 from pandas import *

/Library/Python/2.7/site-packages/pandas-0.5.1.dev_5abb534_20111104-py2.7-macosx-10.7-x86_64.egg/pandas/__init__.py in <module>()
     20 from pandas.info import __doc__
     21 
---> 22 from pandas.core.api import *
     23 from pandas.core.common import set_printoptions
     24 from pandas.core.common import set_eng_float_format

/Library/Python/2.7/site-packages/pandas-0.5.1.dev_5abb534_20111104-py2.7-macosx-10.7-x86_64.egg/pandas/core/api.py in <module>()
      6 import pandas.core.datetools as datetools
      7 
----> 8 from pandas.core.common import isnull, notnull, set_printoptions, save, load
      9 from pandas.core.index import Index, Int64Index, Factor, MultiIndex
     10 from pandas.core.daterange import DateRange

/Library/Python/2.7/site-packages/pandas-0.5.1.dev_5abb534_20111104-py2.7-macosx-10.7-x86_64.egg/pandas/core/common.py in <module>()
    111 
    112 _take1d_dict = {
--> 113     'float64' : lib.take_1d_float64,
    114     'int32' : lib.take_1d_int32,
    115     'int64' : lib.take_1d_int64,

AttributeError: 'module' object has no attribute 'take_1d_float64'
```
