ENH: Implement FloatingArray reductions
Mostly copy / paste from https://github.com/pandas-dev/pandas/pull/36761

@jorisvandenbossche Would this require a whatsnew note? Seems the current v1.2.0 note is fairly high level and doesn't talk about specific methods that are supported. Should we talk about this or leave as-is?
actually if you rebase I think you can push these down to BaseMaskedArray entirely (or factor out to NumericMaskedArray if need to avoid the bool collision issues) great ping on green. thanks