e500 port plans

[Roland McGrath]

> The two changes (e500 port, and moving powerpc bits out of ports/) seem 
> completely independent to me.

They are.  But we need to get the ball rolling on migrating things out of
ports somehow, and adding more things into ports/ does not help.  Migrating
the powerpc bits out of ports/ seems far simpler than the other cases there
(because it's not the whole port that is in ports/, but just a few pieces).
I suspect it's not much more than just actually moving the files.