Issue #007: Set up code coverage and coveralls

Adds coveralls support

* Adds an encrypted `COVERALLS_TOKEN` to `travis.yml` and enabled cobertura and coveralls on after_success
* Adds license information to pom
* Ignores the `MavenModelInspection` error on the repoToken `${env.COVERALLS_TOKEN}` (it's in the environment only in travis, see travis docs)
* Removed unused out-commented executions part of cobertura from pom
* Adds sourceEncoding to pom