added maven/tycho support, added feature project

This PR restructures the project to make headless builds with maven and tycho possible. 

It also adds a feature project to make it possible to distribute it in a p2 repository. 

If you're fine with it, i can host it on our p2 repo: http://p2-dev.pdt-extensions.org.

To build the project, simply run `mvn clean install` in the project root. 

To make it still available via dropins, you'd need to build the project and upload the generated artifact to github and update the link in the readme.