Update changelog
Disable Python 3.2 tests for now

I want to release 0.2.0 so that I can continue working on ZODB, and I've
no time to copy the bytes_as_pickle implementation from _pickle_33.c to
_pickle_32.c.  And also to copy the noload implementation (which,
regrettably, lacks tests).

We can add back Python 3.2 support before 1.0.  We also should add tests
for noload().
Preparing release 0.2
Back to development: 0.3