More Language Definition Enhancements

Please see the commit messages which describe the changes quite well.

Closes #1.

I'd like to have a more different scope for UDFs to built-in functions (because `support.function` is usually colored the same for most color schemes) but apparently I couldn't really find a matching scope either. Maybe you can come up with something better.

FYI, I was using an extention named `.YAML-tmLanguage` which is essentially a language definition in YAML for the ease of doing this by hand. I can add it to the repo if you like because I didn't want to include it. [This](http://hastebin.com/qatepibiji.txt) is what the file looks like (hope it doesn't disappear too soon).

For more information, see https://github.com/SublimeText/AAAPackageDev and https://github.com/SublimeText/AAAPackageDev/pull/13 essentially.