kernel - Major bridging functionality added (bug fixes 2)

kernel - Major bridging functionality added (bug fixes 2)

* Recalculate the port configuration after enabling a member interface,
  fixing an issue where openvpn brings up a TAP interface after
  authenticating the link but whos weights then go unrecognized by the
  bridge.

  The port configuration was already being recalculated after a member
  interface becomes disabled.

* Reinitialize the bridge when the link0, link1, and/or link2 interface
  flag changes state, so the sysop doesn't have to bring the interface
  down and up manually to recognize the new settings.