Haskell FreeType binding

Copperbox revision 420.

More work on the low level interface to FreeType.

I think I need to be a bit more thoughtful about which data structures I marshal to Haskell and which I leave in C especially when the C data structures have internal data. The FreeType type FT_FaceRec isn't marshaled across, instead there are peek functions to read the public fields and as the data is immutable and stays on the C side, there is no need for a Storable instance with poke.

There are probably quite a few structs that I went ahead an wrote the Storable instance for, that shouldn't have one.