Generating Ruby on Rails friendly code

As already quoted in issue THRIFT-468 we are trying to integrate Thrift as our RPC solution into Rails applications. Since Rails uses its own class loading mechanism with require_dependency there should be no regular require within your Rails application (The mechanism requires automatically any Constant you call). I extended the Thrift Ruby generator with a rails option to use require_dependency instead of require. In addition to this I basically changed the generated folder structure. Like in Java for instance you should nest namespaced classes in a directory structure which represent that namespace. Due to this is valid even for non-Rails related code I integrated this feature without any switch. But it is especially relevant for Rails, because its auto class loading mechanism expects to find a namespaced class under an appropriate directory layout within the load path.

I'm not a C++ guy so I would be really thankful if you could give me some useful feedback to this patch.