Getters for ServerGame. Also bases can now be damaged 
(A note on bases: they're not an object the game keeps track of. They're
just squares on the board with particular properties including their
level of damage and their owner. A ship can repair if it is adjacent to
an undamaged basesquare belonging to the same player as itself.)
Merge branch 'master' of https://github.com/etiennefd/Battlesheeps.git
Nothing