Add testscenarios library

This commits add the testscenarios library to support a view all tested
variations. This will change the following:

 - json_generator adds a test name for each variation
 - a class must be created for each scenario
 - list and execute of test variations are separated from now on
 - pep8 ;)

TODOS:

 - Create base class for negative tests (this will eliminate all dup code)

Change-Id: Ibc90ec014cfdc01c9a1fac3cccbeaecb2a4c97a1
Signed-off-by: Marc Koderer <m.koderer@telekom.de>