BUG: fixed append for dataframe with multi-column
Merge pull request #6167 from wabu/append-multi-fix

append to existing table with mulitindex fix
TST: sparc fixes in datetime weirdness
BUG: Consistency with dtypes in setting an empty DataFrame (GH6171)
BLD: try harder to find errno in @network
Merge pull request #6172 from jreback/empty_frame

BUG: Consistency with dtypes in setting an empty DataFrame (GH6171)
BLD/TST: @network, SkipTest on certain exception messages, when no errno set
TST: set default socket timeout to 5 sec in pandas.io.tests SetUp()
Merge pull request #6174 from y-p/PR_more_network

More @network fixes
CLN: use assertEqual over assert_ for better exception messages
ENH: Add sym_diff for index
DOC: numpy docstring format for Index.diff