ENH col_level argument to melt
ENH MultiIndex columns with melt
FIX disallow MultiIndex in Series constructor GH4187
BLD: pip 1.4 is coming, preempt issues

https://github.com/pypa/pip/issues/974
Merge pull request #4210 from y-p/PR_pip14

BLD: pip 1.4 is coming, preempt issues
DOC: remove savefig width parameter (#4203)
DOC: minor io.rst edits
BLD: Turn off the ISRELEASED flag in setup.py
CLN/ENH: clean up docstrings remove some cruft and generalize
Merge pull request #4150 from hayd/melt_multi

ENH: Melt with MultiIndex columns
TST: little endian failure, GH4222
Merge pull request #4228 from jreback/stata_bug

TST: little endian failure, GH4222
Merge pull request #4190 from hayd/disallow_multi

FIX disallow MultiIndex in Series constructor GH4187
BUG: raise on invalid colormap for older mpl
DOC: release notes
CLN: correct format string
Merge pull request #4231 from cpcloud/matplotlib-invalid-colomap-test

BUG: raise on invalid colormap for older mpl
BLD: test_perf tweaks
TST/BUG: disallow bs4==4.2.0 and skip assoc tests
BUG: Display the legend when calling plot with kind='density'. GH4216