BUG: fix transform with integers
Merge pull request #7973 from cpcloud/transform-oddity-7972

BUG: fix transform with integers
PERF: perf improvements for Series.transform (revised) (GH6496)
Merge pull request #7975 from jreback/transform_perf

PERF: perf improvements for Series.transform (revised) (GH6496)
BUG: Allow __name__less callables as groupby hows (GH7929)
Merge pull request #7974 from dsm054/allow_nameless_callables

BUG: Allow __name__less callables as groupby hows (GH7929)
BUG/ENH: fix ewmvar/cov debiasing factors; add 'adjust' to ewm*() functions