Minimal refactor of renderer to prepare flexgrid

Minimal refactor of renderer to prepare flexgrid

- Move NetworkModelWavelengthService to networkmodel as topology update
  must be done by this module.
- NetworkModelWavelengthService is now invoked by a notification sent
  by service handler instead of being directly called by renderer
- Update constructors when NetworkModelWavelengthService is no more
  used.
- Remove no more used methods from RenderServiceOperations and its
  implementation.
- Update RenderListenerImpl from service handler to send notification
  for network model.
- Add a service listener to networkmodel to update frequencies map in
  topology.
- Minimal update to unit test after moving class
- Move MountPointStub from renderer to test-common
- Update blueprint files of render, service handler and network model

JIRA: TRNSPRTPCE-230
Signed-off-by: manuedelf <emmanuelle.delfour@orange.com>
Change-Id: I9dda66a301d92b74795ee5f239699bc2d11e9a8e