[Twisted-Python] Subproject releases

[Glyph Lefkowitz]

Matt Goodall wrote:

> Anyway, let's not let this descend into a setuptools vs <insert
> favourite package manager> flame fest. Making eggs possible are just one
> of many goals that may be helped by separating Twisted projects.

It would also probably simplify the existing setup.py installations, but
agreed: let's not conflate the two discussions.

However, as long as we're talking about it... mg: What you did for Nevow
would probably be a good idea; let's have a parallel setuptools_setup.py
for a while before switching over to it.

eggs are pretty awesome though, twisted.plugin should definitely have
some way of integrating with them.  As far as dropin.cache goes, I have
some weird ideas about a "path management object" that wrapped around
sys.path and did things like determine if zipimport was being used at
any point in any path, to give parallel directories to write cache data
to, etc.  __file__ references can be replaced by
get_resource_mumblemumble calls entirely, right?

FWIW: I do mostly remember arguing against this initially ;-), and I
think it was probably a good idea at the time.  The "topfiles" idea was
pretty ingenious to keep the whole repository working with the same
structure between 1.3 and 2.0.  I just think its' time has passed.

and David, I did read the code to Pthy before I wrote Combinator, so
that project did help :-)