BUG: Fix a bug when indexing np.nan via loc/iloc (GH5016)
ENH/CLN: Give AssertionErrors and nose.SkipTest raises a message
Merge pull request #5018 from jreback/column_nan

BUG: Fix a bug when indexing np.nan via loc/iloc (GH5016)
Merge pull request #3730 from cpcloud/parse-exceptions

ENH/CLN: give all AssertionErrors and nose.SkipTest raises an informative message