TST/BUG: allow invalid Timestamps to pass thru as datetimes when operating with offsets
         related (GH5312)
Merge pull request #5327 from jreback/timestamp_offset

TST/BUG: allow invalid Timestamps to pass thru as datetimes when operating with offsets
CLN: Fix return type for initObjToJSON()
Merge pull request #5334 from jtratner/try-fix-for-initobjtojson

CLN: Fix return type for initObjToJSON()
BUG/CLN: Refactor sanitize_column broadcasting

And only try to broadcast if columns aren't unique or are MI.

(also in the process fix small bug from #5321)
Merge pull request #5341 from jtratner/tweak-sanitize-column

BUG/CLN: Cleanup sanitize column and abstract broadcasting
BUG: Bug when renaming then set_index on a DataFrame (GH5344)
Merge pull request #5345 from jreback/rename_bug

BUG: Bug when renaming then set_index on a DataFrame (GH5344)