Remove Java support (the JAVA option and CATEGORY) from this port.

Four years after GCC 4.6 went end-of-life upstream there isn't really
much use of that any more since newer ports still carry it, and it
speeds up build and simplifies this port significantly.

In addition to the expected changes to Makefile, pkg-plist, and pkg-descr
this also gets rid of files/java-patch-hier.