Extend to other languages

Create a module to extend this hook to other languages, such as javascript, python, etc.

Remember that this is a git-hook, the solution submitted should be easy to install. Up untill now, we have a single `main.rb` file with execution permissions. If you want to add a new module, and the file gets bigger, you should provide a Rakefile to build the executable.

Take a look at the "Projects" page.