imports of test modules now import from the test package. Other
related oddities are also fixed (like DeprecationWarning filters that
weren't specifying the full import part, etc.). Also did a general
code cleanup to remove all "from test.test_support import *"'s. Other
from...import *'s weren't changed.
another change (to test_import.py, which simply imports the new file). I'm
checking this piece in now, though, to make it easier to distribute a patch
for x-platform checking.