stronghold buff/ balance

[Dhruv patel]

the buff: the tallest tower could be configures to another damage type depending on your style. a cannon with equal damage to your strongest cannon present, a tower with damage set again the same as the highest level tower present or a redoubt with library research supress troop movement

all equal to the range of the stronghold of 8. and on destruction makes rubble slowing down invaders at a range of 3 or so.

the balance or nerf depending on prefrence: if you destroy the stronghold before troop tactics showup they get a hp penalty like the castle.