Add resourceType function for convenience in Eff
Merge branch 'master' of github.com:idris-lang/Idris-dev
Fix for name shadowing in evaluator

Things are much easier if we have unique names everywhere, but we didn't
quite have it right in the evaluator (it wasn't checking the outer
environment when evaluating in a surrounding environment).

Fixes #642
Merge branch 'master' of github.com:idris-lang/Idris-dev