BUG: Fix to_datetime to properly deal with tz offsets #3944

Currently for certain formats of datetime strings, the tz offset will
just be ignored.
CLN: clear up some cython warnings
CLN: eliminate bootstrapping issue form generate_code.py
CLN: test_timeseries_legacy, specialize assert_

GH6175: replacing "assert_" with specialized form assertEqual. WIP: have not adjusted any instances of assert_( (... == ...).all() )
CLN: test_timeseries, specialize assert_

GH6175: replacing "assert_" with specialized form assertEqual. WIP: have not adjusted any instances of assert_( (... == ...).all() )
ENH: add support for Python 3.4 ast.NameConstant
DOC: Py2/3 examples compat (datetime, print, StringIO/BytesIO, range)
Note for failing numpy.unique and fix for pandas.Series NameError
BLD: setup.py version strings. handle shallow clones and installing from sdist
Merge pull request #6217 from y-p/PR_setuppy_version

BLD: setup.py version strings. handle shallow clones and installing from sdist
Merge pull request #6176 from y-p/PR_cython_warnings

CLN: clear up some cython warnings
ENH: pd.read_clipboard detects tab-separated data (excel) GH6223
Merge pull request #6226 from y-p/PR_clip_excel

ENH: pd.read_clipboard detects tab-separated data (excel) GH6223
Merge pull request #6201 from bwignall/assert_6175_3

Change more assert_'s to specialized forms
CLN: Changing some 'assert_'s to 'assert[Not]Equal', as per GH6175
CLN: test_plotting, specialize assert_

GH6175: replacing "assert_" with specialized forms of assert
CLN: test_resample, specialize assert_

GH6175: replacing "assert_" with specialized forms of assert. WIP: calls with assert_( (...).all() ) have not been changed.
CLN: test_timedeltas, specialize assert_

GH6175: replacing "assert_" with specialized form assertEqual.
Merge pull request #6198 from  bwignall/assert_6175_2 (reworked)

* bwignall-assert_6175_2:
  CLN: test_timedeltas, specialize assert_
  CLN: test_resample, specialize assert_
  CLN: test_plotting, specialize assert_
  CLN: Changing some 'assert_'s to 'assert[Not]Equal', as per GH6175
Merge pull request #6230 from phaebz/PR_py3_doc_compat

DOC/PY3: Python 3 docs example compat for range, StringIO and datetime