allow configuration of max_vm_flows through salt-formula

the value of max_vm_flows is currently not configurable through
salt-formula-contrail. this allows single instances to fully overload
the compute node with contrail flows, blocking traffic to other
instances on the same compute node. making this setting configurable
allows us to better protect our compute node against this overload of
flows

Change-Id: I5db2f99c94ae27ca8436a193c03bcb0b8b8b84d6
3 files changed