Move to maven project configuration

- Move tests to separate Maven modules
- There is a JUnit test project with Robolectric now as well as a separate
  project for instrumentation tests, which need to be run on an emulator
- Everything works now in Maven as well as in Eclipse
- The instrumentation tests are run automatically if the whole project is built
- The main application can be built separately

This is the result of the pair programming session with Stephan Stiboller on
21/05/2013.