FYI: RMIC

[Tom Tromey]

I just checked in some code that lets the rmic program actually invoke
the Java compiler.  It is based on the interface already exposed in
RMIC.java; I didn't read the kaffe implementation to write this one.
I also changed it a little bit.

Right now I've only added a concrete implementation for gcj.  Adding a
new one is very easy; I encourage others to add the compilers they
care about.

Tom