Updated Java target

Added some fixes to get the Java target working, but some things don't
work yet. I marked those using a "//FIXME:".
Fixed Kore keys.
Expose the Loader.
[Kore] Catch Return key in addition to Enter key.
Merge https://github.com/kirby0016/Kha
Merge branch 'master' of https://git.ktxsoftware.com/git/KOM/Kha