[Python-3000] ref counts

[Neal Norwitz]

I'm starting up a continuous build of sorts on the PSF machine for the
3k branch.  Right now the failures will only go to me.  I've excluded
the two tests that are known to currently fail.  This will help us
find new failures (including ref leaks).  Probably in a week or so
I'll send the results to python-3000-checkins.  Since it's just
running on a single machine (every 12 hours), this should be pretty
stable.  It has been for the trunk and 2.5 branch.

I just wanted to point out some data points wrt ref counts.

At the end of a test run on trunk with 298 tests the total ref count is:
  [482838 refs]

When starting a new process (like during the subprocess tests):
  [7323 refs]

With 3k and 302 tests:
  [615279 refs]

and:
  [10457 refs]

I don't think these are problematic.  I expect that these ~30%
increases in total ref counts are primarily the result of new-style
classes.

n