Implement Enemy Spawn Selection
The map generator will now choose random cells to be enemy spawn locations, up to a number of spawns less than a defined percentage of the total possible enemy spawn locations. Enemy spawns are never closer than a pre-defined distance from the player's spawn and never directly adjecent to a hole. The tilemap script also will ensure that enemies never spawn inside a collidable tile. This means that enemies will never spawn trapped inside of the level geometry.