Add Kingdom:when a player's islands are all taken by someone,it will become a member of the invader's kingdom.Player can betray his kingdom or surrender to other kingdom.When a player join a kingdom,he can see the whole map of the allies.
Add battery,attack island cost 1 battery,surrender cost 5,betray cost 10.Battery will recover everyday,limitation is 10
new born ship collide with others bugfix
new ship born outside map bugfix
ship with no core device crash game bugfix
main menu disappear bugfix