Fix scenarios not passing down specific network

Nova v2 api expects nics in specific networks to be passed
down in an array of "networks". nics is used in novaclient
but converted to networks in
python-novaclient/tree/novaclient/v1_1/servers.py#n520

Apply the conversion to the parameters to make the check
pass in case where there would be multiple networks
matching the requirements. Also remove a case where scenario
manager forced in the wrong network into the tests.

Closes-Bug: #1368834
Change-Id: Ic0b87377c5878e240a0fbcc6549023c828dd97ab
Merge "Fix scenarios not passing down specific network"