API: return None when inplace=True. re #1893
BLD: tox, don't clean up build dir, permissions often get in the way
TST: check and raise on df.applymap with df having dupe columns
BUG: check and raise on df.applymap with df having dupe columns
Merge pull request #3212 from wesm/inplace-not-return-self

API: return None when inplace=True. closes #1893
TST: more robust tests in HDFStore

TST: print output on exception
Merge pull request #3226 from jreback/hdf_test

TST: more robust tests in HDFStore
BUG: KDE plot fails with color kwarg #3187
TST add regression test for GH2753
Merge pull request #3227 from hayd/GH2753

TST add regression test for GH2753