intersperse
intercalate
Merge branch 'master' into intersperse

Conflicts:
	classy-prelude/ClassyPrelude/List.hs
foldable-based intercalate
Merge branch 'concat' into intersperse

Conflicts:
	classy-prelude/ClassyPrelude/Vector.hs
CanConcat-based intercalate
Merge branch 'intersperse' of https://github.com/nikita-volkov/classy-prelude

Conflicts:
	classy-prelude/ClassyPrelude/Classes.hs