Since multus now handles pods as a long lived state machine, we need to see the result of multiple plug / unplug operations in the lifetime of the pod. 

As such, we need to introduce some pod status conditions for added / removed interfaces.

The following schema is proposed:

• HotplugInterface
  • network
  • ifaceName
  • Status
  • DetailedMsg (only on "failed" statuses).
  • Timestamp

• status enum
  • started
  • failed
  • succeeded