[Piglit] Time to switch to Python 3 already?

[Matt Turner]

It was more than a year ago now [1] that we agreed to "hold these
patches back for a short time (maybe a month) to give people time to
get ready for the transition"

In the mean time, we've struggled with Python 2.7 regressions and
dealt with many "this breaks with Python 2.6" comments. Is it time to
finally stop?

RHEL people seemed to want to continue with Python 2.7 support. Time
to make a 2.7 branch that you guys can maintain on your own without
causing problems for Mesa developers using piglit every day?

[1] http://lists.freedesktop.org/archives/piglit/2013-April/005402.html