BUG: remove six import
ENH: Add `isin` method to DataFrame.

docs. to be rebased

ENH: Add isin method to DataFrame

Basic tests.

Added method and fixed tests.

ENH: Add ordered argument to df.isin()

Expects a sequence of arrays.

Updated release notes for df.isin()

CLN: cleanup

going to remove ordered argument.

Using a dict for ordered matching. Docs

BUG: fixed subselection length check issues.

Updated release notes for df.isin()

remove merge conflict note
ENH tweak DataFrame isin method
TST: no need for flavor testing in skip

Skip bs4 tests when 4.2.0 is found.
DOC: add v0.13.0.txt release notes file (but not to the index yet)
ENH add iloc argument to DataFrame isin
BLD/TST/CI: add script to show skipped tests at the end of a build
TST/BLD: add testing for bad bs4 version
TST: add message to nose.SkipTest
CLN: define __hash__ directly for _NaT; needed for some builds on py3k
TST: skip if no html5lib since bs4 needs it
TST/CI: add scikits.timeseries wheel back
TST: properly skip html5lib
TST/CI: remove html5lib from 3.2 build
DOC: cookbook example
BUG: fix data.py regression
BUG: Fixed non-unique indexing memory allocation issue with .ix/.loc (GH4280)
TST: ujson dont force endianness #4274
Update CONTRIBUTING.md with note on attribution in PRs
DOC: Fix typo.