Fuzz test roundtrip conversions between C & Haskell datastructures!

Properly handle ambiguity in empty char/lang sets.

Improve memory safety & error checks.

Write init/finalize & pattern language bindings, haskell-side!

Draft C-side wrappers for various FontConfig APIs.

Continue implementing C-side language bindings.

Implement a scanner on C-side (LibCMP doesn't provide it).

Fix C code, it compiles now!

Encode & decode FontConfig data on C side.

Encode & decode charsets on C side (fix Haskell side)