Fix crash caused by AA tank, so it can be enabled again#11

It would be nice to have AA tank available to buy.

Yea, however there is something wrong with aaa. When a player is shooting with aaa (under the ssm cryfire), it cause the server’s crash. There was also this problem on !hotspot server.

Currently, I have still no idea why it crash the server.

The GaussRifle was buff a lot to replace aaa, 4 shot with GaussRifle is enought to destroye a vtol, I think it’s fine.