Changes to move to GHC 7.8

Upgraded to compile with GHC 7.8 and cleaned up the code base.  Added
minimum version numbers for all packages.
Merge branch 'build-issues' of https://github.com/galoisinc/pads-haskell

Conflicts:
	.gitignore
Merge branch 'master' of https://github.com/galoisinc/pads-haskell