Renames juxtapose to follow (and precede), adds (>|), misc
Adds Data.AffineSpace.Point to Music.Score reexports
Changes Score.Composeable to (correctly) sort its input

(Should add this to docs)
Docs
Remaned events to performValues

I am not done with the Performable class yet: I want to formalize
the relation to foldable (as we did with Monoid/Pointed) in Composable

The performValues should be superseded by toList without adding any extra
constraints to combinators using (Performable) =>