A small update

Based on player feedback, tank health has been equalized across all targets.

Now tanks on defense, railway stations, bridges, and all other targets have the same HP as they do on attacks.

Now tanks will have to be dealt with using heavy weapons (bombs, missiles, heavy guns). Consequently, the reward for destroying them has been increased fivefold, making them almost the most expensive target to destroy on the server (only ships are more expensive).