Start versioning and releasing new versions

[rpannek]

As a user it is somewhat difficult to know if the master branch is compatible with my application or if it will break my code, and which version I need to use.

It would be nice if you started releasing versions according to for example http://semver.org/

Github makes it really easy, once you create a tag and push it, it creates a special release page where you can put your release notes, etc. and it creates a tarball and a zip package for it so people who package stuff for distributions have an easier way packaging it.