[Added] PetControlDevice, PetControlObserver, and CallPetTask
[Added] stormtrooper and rebel trooper faction pets for purchase at
recruiters (temporary, for testing of the control devices. They don't do
anything but follow right now)

Change-Id: If486e408c1eae93d281395c12ae32308cc73a79a
[fixed] mantis 4304 tabage scavengers have leathery hide

Change-Id: I3f641c15a27ab7b74c9845f7e8ff215cdcc8ab9e
Merge "[fixed] mantis 4304 tabage scavengers have leathery hide" into unstable