Remove project group creation requirement
Simple network handling in OpenStack backend

The implementation is subpar yet.
The network and a corresponding subnet are only created
if no network is with the the same name as tenant is present.

No synchronization attempts are performed.

NC-188
Merge branch 'feature/nc-188' into 'develop'

Simplistic network support for OpenStack, NC-188
Merge branch 'feature/project-creation-cleanup' into 'develop'

Feature/project creation cleanup