[Piglit] test profile cleanups, mailny in cl.py

[Dylan Baker]

This started as an attempt for me to check the I hadn't broken cl tests,
and quickly spiraled from there. The basic problem being solved is that
cl.py cannot currently be run outside of the piglit source directory
(such when installed). Patches 1-4 directly address that problem, while
pathes 5-7 cleanup a few things in cl.py, since it's reasonable to work
on that profile.