Wrap runghc

Should also decide how to wrap runhaskel.
Remove duplicated install*GHC*Wrapper blocks
Add missing modules and source files to cabal file
Merge pull request #1 from benarmston/wrap-runghc

Wrap runghc
Merge pull request #2 from benarmston/include-missing-source-files-hsenv-cabal

Include missing source files hsenv cabal
Fix GHC 7.4 compatibility (Prelude.catch issue)