ENH: sql support with SQLAlchemy - follow-up
#5950 is now merged! (Thanks to @mangecoeur)

But there were still some issue to flesh out/fix:
- [x] release notes / 0.14.0 whatsnew (Here is the section in whatsnew for when you are ready): http://pandas-docs.github.io/pandas-docs-travis/whatsnew.html#whatsnew-0140-sql -> #7120
- [ ] figure out user API (#6300) and update api.rst/docs accordingly
  - ~~functional api (read_table/read_sql)~~ (fixed in #6867)
  - ~~other public functions? (execute, has_table)`~~ (see #6300 and #6987)
  - OO API (PandasSQLAlchemy?)
- [x] get travis working (not skipping the tests)
  MySQL was taken out of the 2.7 build, for some reason was failing the build process: https://github.com/pydata/pandas/commit/043d165290180c6d9e3a480c18e220548af56c53, and failure here (see install.sh): https://travis-ci.org/jreback/pandas/jobs/18477137 (note Joris: I think this is OK now with pymysql)
- [x] get MySQL working (failing tests, see https://github.com/pydata/pandas/pull/6316#issuecomment-34960181) -> fixed in #6613
- [x] handle `OperationsError` (e.g. have PyMySQL installed but server is not running) -> #6651 
- lower bar on sql alchemy version -> moved to #6340, #7022
- [x] add postgresql tests (#6316) (and other flavors?)
- [x] move DataFrame.to_sql to generic and update it with new functionality -> fixed in #6598 
- timezone issues (see also https://github.com/pydata/pandas/pull/5950#issuecomment-33630742) -> moved to #7139
- [x] check if relevant parts of old legacy tests pass with master -> #6987
- [x] check coverage of the test suite
- [ ] add vbench (esp. vs old code)
- [x] `columns` argument in `read_table` not working
- [x] use `itertuples` rather than `iterrows` #6509
- [x] error when having integer column names (fixed in #6902)
- [x] read and write a `MultiIndex` (so `index_col` should take a list as well as a scalar) (fixed in #6735)
- [x] Allow mapping as parameters for SQL DBAPI2 #6708 (fixed in #6709)
- [x] Conversion of invalid column names is broken (you get column with None's) #6796, fixed in #6902 
- [x] Data written with to_sql legacy mode (sqlite/mysql) is not persistent (not written, only in memory) #6846, fixed in #6875

There is also a todo list in https://github.com/pydata/pandas/issues/4163, but I thought it is cleaner to start a new one (but maybe we should copy some over). 
Complement the list if you think of others!
