Adjust monasca-notification installation with changes:
- start/stop of monasca-notification proces handles through run_process
and stop_process and no service files
- setting up environment with devstack function
- use USE_VENV for monasca-notification
- installing monasca-notification dependencies from git
- remove service file from devstack/files/monasca-notification
Also added code from Idbe5bdf56fb280412c34f04de8f2e2f301a7a432
Depends-On: Idbe5bdf56fb280412c34f04de8f2e2f301a7a432
Change-Id: Ic581fbdd2db57c9a2f13f1646eb9485c5dd0f62b
f9b41eefbe