Fix for floating ip association and deletion

Added code to associate fip to a vm in VSD, if
the fip was already associated with the vm port
in Neutron. Also added code in fip deletion,
to get the correct router id based on the check
if the fip is associated to a Neutron port or
not.
Closes-Bug: #1350469
Change-Id: I1aa24f420f656043086a4f501b15722216b843e9
Merge "Fix for floating ip association and deletion"