Issue 121: Gradelize the project

[ghost]

121

The build is almost ready: I still need to figure out a couple of minor things, but all checks, tests, reports are here. Also, I am adding the wrapper script so you don't have to install gradle into your environment.

Once the patch is in place one can run ./gradlew install to generate, test, and locally install the artifacts.

[pjeli]

Closing this because it was committed in a separate pull request.