[Piglit] log-refactor v2

[Dylan Baker]

This is a pretty minor update to this seires. It fixes the things Ilia
requested fixed from v1, and makes the series behavioral change neutral.
-v/--verbose is back, and the status line in verbose mode works as it
did before.

I have also done some benchmarking to get status numbers.

I created a set of 10 tests that are based a very simple Test derived
class (it sets interpret_result = self.result['result'] = 'pass')
Then I ran 10 tests where the command was set to 'bash -c "sleep 1"'.
Each test was run once as a warm up, to ensure that all of the pyhton
bytecode had been generated before running tests. This gave me as close
as possible to a controlled environment, I ran each test 5 times,
averaging them, measuirng them with the unix `time` command, and using
'total time'. all tests were run with -c on an IvyBridge with 4 threads.

(in seconds, rounded to the nearest thousandth)
Master default: 3.493
branch quiet  : 3.466

Master verbose: 3.485
branch verbose: 3.483

This is available at my github:
https://github.com/dcbaker/piglit.git submit/log-refactor