maven sample with Java sample codes

[danyaljj]

I wish the maven sample had examples also containing java files, in addition to scala files.
I tried adding something very quickly, but will give it another try.

[danyaljj]

I myself create one btw: https://github.com/danyaljj/sampleMixedScalaJavaMavenProject

[SethTisue]

I think it's better to keep this repo focused on demonstrating Scala module use only, and not include other things in the templates. That is valuable to do — but elsewhere.