[Piglit] Python PEP 8 compliance

[Dylan Baker]

This very long series of patches fixes a very large number of python
PEP 8 violations, while leaving a few behind. This is meant to create no
functional changes, only cosmetic ones.

Anytime a PEP 8 violation remains the reasoning is given in the git
commit log, as well as where that violation is. Mostly these violations
are in docstrings, and usually they are non-python code (c++).

This series is tested to compile, and all.tests and quick.tests produce
no variation on intel ivybridge with the mesa 9.2 development branch.
However, I have no way to test the CL tests, and it is entirely possible
that I regressed them somehow.

this branch is available from git:
https://github.com/crymson/piglit.git pep8