Handle conflict in network creation
Store restricted instances of Cloud in test_tenant_cloud dict
Fix fake back-end behavior with floating IPs

Fake back-end cannot assign floating IP to server without excplicit
specification of fixed IP to associate the floating IP with.
Fix formatting issues (PEP8) in fake.py
Add project_id to support filtering for nova.networks.findall() method
Delete floating ips from prefixed pools on cleanup
Reuse floating ip pool name and create floating ip in tenant
Retry assigning floating ip until server net info is created
Pass floating ip address as string to bulk delete
Fake floating ips can be associated to project (floating_ips.create)
Merge improved handling of networks and floating ips on setup