DOC: Add common error message to byte-ordering gotcha.
Merge pull request #6521 from danielballan/endian-gotcha

DOC: Add common error message to byte-ordering gotcha.
- Cleaned up ambiguous _offset_map

- Add test showing issue with period index construction

CP

CP

fix compat issue

CDate might not be defined

remove some circularity

Further simplify

Another example of PeriodIndex issues

- Fixed issues from rebase

- Additional test for DateOffset and DateOffset's repr equality with
aliases

Pass freq objecr around; added mixin for non Cython periods

- fix build. save off missing freq_obj

factored out _check_mult
word on asfreq

work on _NonCythonPeriod

- work on _NonCythonPeriod
- added methods from _NonCythonPeriod to FY5252Quarter

- upsampling from FY5253Quarter to Week works
- testing for new period support

- fix assertion for py26
- fix division for python3

- cleaned up inferred_freq_offset property

- fix tests to work on py3

work on periods

Fix Issues with FY5253 and nearest w/ year end in Dec

CP work on down sample

- Finished support for downsampling

- fix bad int literal

- more testing of periods
- handle asfreq=start

- upsample and downsample from FY5253Quarter to Day

- factored out _try_parse_qtr_time_string for reuse
- added parse_time_string to DateOffset
-- Can now index FY5252 by string