Cleanup repo - multiple changes

This builds on top of #2. Changes introduced:
- Cucumberl features rewritten as Common Test tests (errr, one was broken and still is)
- removed most, now unused, dependencies - this should shorten dependency resolution/build times of projects dependent on this one (read: MongooseIM ;)
- removed Ruby artifacts - this is an Erlang lib after all and most of these tools probably wouldn't be available
- redirected Travis and GitHub URLs in README.md to ESL repo instead of Madtrick repo
- tweaked `.travis.yml` to do a Dialyzer check

What I don't know is how to make Travis build this repo. I think it doesn't list it as an ESL project as it's just a fork of another repository. Any ideas?