Named type class instances
Merge branch 'master' of github.com:paf31/purescript

Conflicts:
	RELEASE-0.5.md
Update docs
Update typeclasses.rst
Bump version
Fix issue with readNumber
Fix the types and implementations of some Prelude functions in the Math module.
Rename "ImportType" so semantically it works for exports too
Initial work for module exports
Basic tests for module exports
Explicit exports
Disallow export of undefined members
Reject invalid qualified names