[PEAK] Upgrading required Python version

[Phillip J. Eby]

Hi all.  I'm thinking about bumping the version of Python required for 
PyProtocols and PEAK.  Does anybody besides me actually still use 
2.2?  And, would anyone see a problem upgrading to 2.4?

Currently, PEAK and PyProtocols both include stuff cribbed from 2.3 and 2.4 
that it would be nice to forget about, and there are lots of features added 
later that it would be nice to take advantage of.  Also, there are plenty 
of other packages out there (e.g. ctypes) that only work with 2.3 and up.

Last, but not least, 2.3 supports importing from zipfiles, and 2.4 should 
actually allow PEAK to lazily import from zipfiles.  (As should 2.3.5, but 
that version doesn't actually exist yet.)

Anyway, 2.2.2 is now over 2 years old and beginning to show its 
age.  Personally, I'm thinking maybe we should just bite the bullet and 
jump straight to 2.4 so that we can use decorators and generator 
expressions, as well as avoiding the need to build our own special versions 
of doctest and pyexpat just to get the 2.4 versions' features.

Any thoughts?