Add support for 1- and 2-byte unsigned integer typedefs.
Add support for 1- and 2-byte unsigned integer typedefs.

ocamllabs/ocaml-ctypes,yallop/ocaml-ctypes,yallop/ocaml-ctypes,dsheets/ocaml-ctypes,dsheets/ocaml-ctypes,whitequark/ocaml-ctypes,ocamllabs/ocaml-ctypes,dsheets/ocaml-ctypes,whitequark/ocaml-ctypes,whitequark/ocaml-ctypes