Remove support for Java

[eikek]

Since the company where I'm working decided to not use this anymore and rather go with gradle, I don't need support for Java and thus don't want to maintain it.

I guess this is not used by many anyways and then it is unlikely that java is needed. So I'm going to remove it during the next weeks or so. If, against all the odds, someone still needs it/wants it, please let me know.