Remove copy-pasted requires; Run tests; Trivial fixes
    
    - Don't own __pycache__ directory in python3 subpackage
    - Really run tests (setup.py test doesn't do anything)
    - Drop copy-pasted Requires (RHBZ #1405639)
    - Trivial cleanups
    
    Signed-off-by: Igor Gnatenko <i.gnatenko.brain@gmail.com>