Ok, here are the patches. Since it's a combination of renaming and
removing, I had to improvize a little, particularly in the 2.6
documentation. Hope it's done correctly.

I still have doubts about the following issue, as commented in
test_commands.py :
# The module says:
#   "NB This only works (and is only relevant) for UNIX."
#
# Actually, getoutput should work on any platform with an os.popen, but
# I'll take the comment as given, and skip this suite.

I played it safe as well and didn't change the platform test (both in
trunk/test_py3kwarn and py3k/test_subprocess). Should this restriction
remain ?