LOS stuff, security added.

Can't access map unless it is visible to a unit.
If going from a unit, can only access things visible to the unit.
If going from hivemind, can access all seen to nearby units.
Made sure unit stats, hivemind stats, tile stats can't be improperly modified.
X macros for getters where necessary.
Added variables for trees and bushes to map. Trees aren't walkable.