Fix documentation for Planet.owner.
Fix documentation for Planet.owner.

HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II,HaliteChallenge/Halite-II