counting sort instead of np.argsort in left outer join
BUG: GroupBy.count() with float32 data type does not exclude nan
Merge pull request #8171 from behzadnouri/count-f32

BUG: GroupBy.count() with float32 data type does not exclude nan
Merge pull request #8172 from behzadnouri/lj-cnt-sort

counting sort instead of np.argsort in left outer join
BUG: barplot with NaNs
DOC: Table about how plots handle missing data.