[ fixed UU-ComputerScience#71 ] Removed unnecessary ImpredicativeTypes language extension.

This language extension is unnecessary with GHC 7.10.3 and it was
causing compilation errors with GHC 8.0.1 RC 2.

Note: I didn't run the test-suite after this change.

Author: asr

EHC/src/ehc/EHC/BuildFunction/Run.chs

@@ -1,5 +1,5 @@
 %%[0 hs
-{-# LANGUAGE GADTs, TemplateHaskell, KindSignatures, ImpredicativeTypes #-}
+{-# LANGUAGE GADTs, TemplateHaskell, KindSignatures #-}
 -- {-# LANGUAGE RecursiveDo #-}
 %%]