[Twisted-Python] process.py

[Itamar Shtull-Trauring]

I tried refactoring process.Process to support new API, but I gave up - it 
seems kinda broken, i.e. closes when the process's stdout closes, instead of 
when the subprocess dies. Anyway, someone else should fix it. I will do the 
win32 Process. We probably ought to write a few new tests.

Once we do that, and rename all reactor modules, I think we're go for a new 
release.