Migrate to Gradle 1.5

I converted your maven project to gradle :)
As far as things compile/work, they work the same as with your maven build.

With the _./gradlew_ and _./gradlew.bat_ scripts, you don't even have to install gradle. Execute _./gradlew(.bat)_ and gradle will be downloaded and works out-of-the-box. You can upgrade it's gradle-wrapper version by updating the _distributionUrl_ property in _gradle/wrapper/gradle-wrapper.properties_