Add the ability to purge the mgt interface port from OVS
Add the ability to purge the mgt interface port from OVS

DHC-1062

Add the purge_management_interface method to the Quantum
class to make it able to remove the mgt tap interface
from the machine the rug in running on.

Change-Id: Id7ef19b0680a214c2c941e629a7b3b449a4bd914
Signed-off-by: Rosario Di Somma <73b2fe5f91895aea2b4d0e8942a5edf9f18fa897@dreamhost.com>

dreamhost/akanda-rug,openstack/akanda-rug,markmcclain/astara,openstack/akanda-rug,stackforge/akanda-rug,stackforge/akanda-rug