BUG: box datetime64 values in Series.map/apply. close #2627
DOC: add docstring for dtype arg to read_* functions. close #2619
DOC: add note about na_filter in read_* docstrings. #2619
TST: fix failing vbenchmarks. close #2548
BUG: upconvert datetime64 to datetime.datetime when necessary in concat steps. close #2624
ENH: raise a more helpful error message when merging frames with duplicate columns. close #2649
BUG: when parsing partial date, use sane defaults for missing fields GH2618

dateutil uses the current date to fill in missing fields, this
is desirable for year and month, but will cause an exception
when code is run on the 31st day of a month, and trying to parse
"2000 2" as feb 2000, because feb doesn't have 31 days.

So we default to current year and month, but always the first of the month.
TST: unit test for possibly buggy .ix assignment with list of values #2707
BUG: fix groupby segfault on MultiIndex issue #2706
BUG: perf_HEAD reports wrong vbench name when an exception is raised
STY: CRLF