fixing https://github.com/pydata/pandas/issues/5372
ENH/CLN: Redefine str.match, and issue a warning on deprecated default behavior.
BUG: groupby with a Float like index misbehaving when the index is non-monotonic (related GH5375)
Merge pull request #5393 from jreback/groupby_iloc

BUG: groupby with a Float like index misbehaving when the index is non-monotonic (related GH5375)
DOC: Expanded section on string methods in wake of extract/match change.
Merge pull request #5376 from RomanPekar/periodIndex-repr

repr for PeriodIndex does not handle <=2 elements well (GH5372)
BUG: Fix color selection in andrews curve"

fixed bug introduced in b5265a5b84ae1aeaf5fff88f1f9e5872a9b404e6
which change from picking a single random color for the class to
picking a random color for each line.
CLN: Minor touchups to docstrings + use assert_produces_warning
Merge pull request #5224 from daniel-ballan/redefine-match
Merge pull request #5378 from tacaswell/fix_andrews_colors

BUG: Fixes color selection in andrews_curve
BUG/TST: fix downcasting of float-like object array
Merge pull request #5397 from jreback/infer

BUG/TST: fix downcasting of float-like object array