Merge pull request #4091 from cpcloud/fix-share-params-grouped-hist

BUG: pass sharex and sharey in grouped_hist
fixed conflict in sql.py
BUG: GH4098, HDFStore not recreating a datetime index properly when has a timezone
Merge pull request #4099 from jreback/hdf_tz

BUG: GH4098, HDFStore not recreating a datetime index properly when has a timezone
BUG: (GH 4096) block ordering is somewhat non-deterministic in HDFStore, so reorder to the existing store

     if needed
Merge pull request #4100 from jreback/hdf_buglet

BUG: (GH 4096) block ordering is somewhat non-deterministic in HDFStore; reorder to the existing store
CLN: Refactor string methods and add PandasObject

Previous PandasObject becomes PandasContainer. New PandasObject becomes
baseclass for more elements (like Index, Categorical, etc.), moves
string methods to baseclass and subclassing objects need only define
`__unicode__` methods to get all string methods for free (and Py2/3
compatible).

CLN: Cleanup extraneous str methods from Panel

CLN: Remove unnecessary string methods from frame

CLN: Change name of TestPandasObjects --> TestPandasContainer
CLN: Make more core objects inherit PandasObject
CLN: Make Categorical inherit from PandasObject

CLN: Make GroupBy inherit from PandasObject

CLN/ENH: Make Sparse* into PandasObjects

Plus get all the string methods working...

CLN: Index now a PandasObject + str method cleanup

CLN: Make tseries/index fit with PandasObject.

CLN: Use PandasObject in internals + cleanup

CLN: Make Period into a PandasObject + cleanup

CLN: Remove extraneous __repr__ from io/excel
CLN: Have PyTables, stats, & Stata use StringMixin

CLN: Make PyTables unicode safe + add StringMixin

CLN: Make StataMissingValue use StringMixin

ENH: Use StringMixin for addl string methods in stats
DOC: New class hierarchy + StringMixin

DOC/CLN: Remove extra whitespace from v0.12.0.txt

DOC: Add PR issue number too

DOC: Fix spelling error
CLN: Move _constructor checks to PandasObject base
Merge pull request #4092 from jtratner/refactor_string_special_methods

CLN: Refactor string special methods
ENH: (GH3863) Timestamp.min and Timestamp.max return a valid Timestamp
Merge branch 'timestamp_min_max' of https://github.com/SleepingPills/pandas into SleepingPills-timestamp_min_max

Conflicts:
	RELEASE.rst
	doc/source/v0.12.0.txt
ERROR: better error message reporting on inserting incompatible column to frame (GH4107)
TST: Change test_html to use stored data.

+ Change up test decorators so no tests marked as network and slow.
Merge pull request #4108 from jreback/GH4107

ERROR: better error message reporting on inserting incompatible column to frame (GH4107)
Merge pull request #4009 from jtratner/add-network-label-to-test-html

TST: Change test_html to use stored data + mark other
CLN: use how="all" so that things that are not nan in other columns are kept
Merge pull request #4111 from cpcloud/data-dot-py-cleanup

CLN: use how="all" in data.py so that things that are not nan in other columns are kept