Corrected many style violations in the tests.

I focussed primarily on F-category violations, they are all but all fixed with
this patch.

Change-Id: I343f6945c97984ed1093bc347b6def6994297041

test/unit/common/test_bench.py

@@ -16,11 +16,9 @@
 # TODO: Tests
 
 import unittest
-from swift.common import bench
 
 
 class TestBench(unittest.TestCase):
-
     def test_placeholder(self):
         pass