Patch structure and timing for re-adding gcj

[Zopolis0 <creatorsmithmdt@gmail.com>]

Over the past few months I have been working on re-adding gcj to gcc (
https://github.com/Zopolis4/gcj/tree/mster). It is now at the point where
all of the code in gcc/java and the related additions to other gcc files
compiles successfully, although libjava still breaks.

Given that I do not know how long it will be before it compiles
successfully, nor the remaining issues preventing it from compiling it
successfully, I was wondering if it would make sense to submit the gcc/java
(and the related additions) code now, as to have it receive treewide
changes rather than mysteriously breaking when I rebase and further slowing
down development.

This would also allow me to test files in libjava with the system gcc,
among other things, as they make use of several types declared in gcc/java.

Regardless of this, when all the code works, how should I submit it?

My current plan is to have an initial commit re-adding the gcc/java and
libjava directories in the exact state that they were removed, as so to
have a clean history, and also adding the java-related code in other gcc
files in a modern state. Then, a second commit modernising the code in
gcc/java and libjava.