labs: reorder setup_neutron_network.sh

Reorder setup_neutron_network.sh to match the install-guide.

Also following the install-guide:
- Don't install neutron-common which is pulled in as a dependency already.
- Add verbose option for metadata agent, too.

Change-Id: Ieed36c63562d7367bc2aaceba6349c5c46e6bc8b
Merge "labs: reorder setup_neutron_network.sh"