Patching ruby output for GTK+ libs

[jbreeden]

I've forked ffi_gen and made some updates to make it work for the GTK+ libs. This is a work in progress, but I've got some simple sample apps running with it, so I wanted to make available some of the changes I made.

Hopefully this will be the nastiest pull request you ever get... Sorry for the mess. The first commit is mostly header files and whitespace stuff, so I've tried to make comments where actual changes appear. I hope that makes it less painful to read through.

My main changes were

• Adding an option to disable function-like macro generation (it doesn't always work, but you also don't always need it. I prefer to disable it rather than not use ffi_gen at all)
• Updated ruby output for macro tokens (macros may have param names like "class" that need to be converted for ruby)
• Turned some failure cases into warnings, like attempts to generate ruby classes for unnamed structs/unions. (Again, I'd rather do without certain features that aren't working than abandoned ffi_gen completely.)

I'm perfectly happy working off my fork of ffi_gen to make my GTK bindings, but if you want to integrate some of these changes I'd be glad to work with you to make that happen.

Cheers!

[jbreeden]

Made the mistake of making this request off my master branch, so it's pulling in everything I do. Plus, as mentioned, it's a huge mess. I'll close this for now. The changes from the original request were mostly one-two liners, but if you want separate pull requests let me know.