Feature/vlan filter call api

This branch add the support for web api call from the vlan filter. Per example it will be possible to change some information in the node or create a violation.

Update:
Description
---------------
This branch add call to the web api:
Take action in the vlan filter

Impacts
----------
no

Delete branch after merge
----------------------------------
YES
violation_trigger instead of trigger_violation since it is calling PacketFence 'violation_trigger' internal method ?