Due to the hacking version update several pep8 checks where ignored
in the flakes8 section of the tox.ini. Removed ignored checks and fixed
appropriate pep8 issues.
The list of fixed issues:
- H105 Don't use author tags
- H238 Old style class declaration, use new style (inherit from `object`)
- H501 Do not use self.__dict__ for string formatting
Closes-Bug: 1530719
Change-Id: I890ba4c54b0da10060767620ff5ff7e480d79a9c