Merge pull request #55 from jrozner/master

Generate pkg-config for Hammer
Merge pull request #56 from jrozner/master

Clean up pyc
Install internal headers for Go bindings

Go, and likely other language bindings will, need access to create
new combinators. This functionality is currently located
src/parsers/parser_internal.h. Install this header to the system with
dependent headers until a better solution can be found.