Log Message:
Convert the Java related packages to use the alternatives system.  To do
this, we only need some simple logic in java-env.mk to automatically
generate an ALTERNATIVES file for us.

There are two exceptions, though: fastjar and jikes (pointed out by tv@),
which do not use this file; they have to be handled manually.

Bump PKGREVISION for all affected packages.

While doing this, remove the java-wrapper package, obsoleted by the new
functionality provided by pkg_alternatives.