Remove Java support (both in terms of the JAVA option and everything
associated with it as well as java from CATEGORIES).

In addition to changes to Makefile, pkg-plist, and pkg-descr, this also
removes files/java-patch-hier.

GCC 4.9 was first released in summer 2014 and went end-of-life upstream
a year ago, but GCC 5 is very well established by now and also provides
support for Java (GCJ/libgcj), and so does GCC 6, and this simplifies
this port significantly and also speeds up the build.

While we are here, streamline the setting of INFO.