Awesome enty

Oops, I will have another go at fixing it for my next release!

I've downloaded Java 13, I can now run battles for BeepBoop. After rebuilding the robot-database, also Raven and WaveShark run fine. Note that for my development I will still use the compiler option '-source 1.8'

Ok, great! I compiled 0.11 with --release 8, but I think it didn't work because there were some old .class files lying around that didn't get overridden.