added create_network method. This is a one stop show for creating a network. It will check if the network exists and if so it will not attempt to create, but if it doesn't exist it will create it.
added create_network method. This is a one stop show for creating a network. It will check if the network exists and if so it will not attempt to create, but if it doesn't exist it will create it.

rcbops-qe/horizon-selenium