Solve all flake8 warnings (#163)

Whipper is now fully PEP8 compliant.
Revised version which includes all the changes suggested by Freso.

whipper/test/test_program_cdrdao.py

@@ -1,14 +1,12 @@
 # -*- Mode: Python; test-case-name: whipper.test.test_program_cdparanoia -*-
 # vi:si:et:sw=4:sts=4:ts=4
 
-import os
-
 from whipper.program import cdrdao
-
 from whipper.test import common
 
 # TODO: Current test architecture makes testing cdrdao difficult. Revisit.
 
+
 class VersionTestCase(common.TestCase):
     def testGetVersion(self):
         v = cdrdao.getCDRDAOVersion()