alex: update to version 3.1.3
happy: update to version 1.19.2
all-packages.nix: cosmetic, no functional change
Fix references to haskell-opengl 2.9.1.0.
ghc-head: update to today's git snapshot and arbitrarily dub it version 7.7.20131202
haskell-packages.nix: cosmetic
haskell-GLUT: update to version 2.5.0.1
haskell-packages.nix: disable transformers 0.3.0.0 when building with GHC 7.7 or later

It's a core package now.
haskell-packages.nix: update 'cgi' to version 3001.1.8.4 when building with GHC 7.7 or later

Not that it helps much ... the package depends on MonadCatchIO-mtl, which is
broken in the latest version of GHC.
haskell-packages.nix: enable dynamic linking in GHC 7.7 or later

The current snapshot requires shared libraries to be built (otherwise
some packages won't build). I'm sure that's a mistake in the way it's
configured that should be fixed. Anyway, enabling shared library support
is an easy way out (and an interesting experiment).
cabal-install: jailbreak version 1.18.0.2 to fix the build with GHC 7.7 or later
async: jailbreak version 2.0.1.4 to fix the build with GHC 7.7 or later
haskell-network: update to version 2.4.2.1
haskell-idris: update to version 0.9.10.1
haskell-postgresql-libpq: update to version 0.8.2.5
haskell-tasty: update to version 0.4.1.1
haskell-zeromq3-haskell: update to version 0.5.1
haskell-cabal2nix: update to version 1.56
haskell-data-pprint: jailbreak to support GHC 7.7 or later
haskell-src-exts: drop obsolete version 1.13.5