BUG: interpolate with no nans and limit
BUG: Bug in putting a PeriodIndex into a Series would convert to int64 dtype, rather than object of Periods (GH7932)
Merge pull request #8235 from TomAugspurger/interp-limit-nonan

BUG: interpolate with no nans and limit
BUG: DataFrame.to_string ignores col_space when header=False

Add test case for when header=False

Make col_space the minimum width of each col

Update release notes
Merge pull request #8237 from jreback/pi

BUG: Bug in putting a PeriodIndex into a Series would convert to int64
BUG: fix groupby crash on duplicated columns (GH7511)
Put all Computation/Descriptive aggregating functions under GroupBy
Merge branch 'master' into groupbydocs