In this patch:
* scenario NeutronNetworks.create_and_list_routers is added,
which does the following:
- creates networks, subnets, routers according to scenario file
- adds routers interfaces to created subnets
- lists routers
* refactoring in NeutronNetworks class for PEP257
and methods arguments
* a piece of rafactoring in ResourceCleaner tests
* classmethod NeutronScenario._generate_subnet_cidr is re-implemented
for using netaddr.IPNetwork class
* base implementation for class fakes.FakeNeutronClient
* some improvements and refactoring for fakes
blueprint benchmark-scenarios-for-neutron
Change-Id: I6dbbe9e476cdf0f1fd4c7f1387e830b5a46e2aa6
4c77a8748d