DOC: fix startrow typo in docstrings
ENH: Period supports NaT
Merge pull request #7485 from sinhrks/periodnat

ENH/BUG: Period/PeriodIndex supports NaT
BUG: Bug in Panel indexing with a multi-index axis (GH 7516)
Merge pull request #7521 from dsm054/fix-startrow-typo

DOC: fix startrow typo in docstrings
Merge pull request #7519 from jreback/mi2

BUG: Bug in Panel indexing with a multi-index axis (GH 7516)
REGR: Regression in datetimelike slice indexing with a duplicated index and non-exact end-points (GH7523)
Merge pull request #7525 from jreback/slice

REGR: Regression in datetimelike slice indexing with a duplicated index and non-exact end-points (GH7523)