Rework T3 Static Artillery to use rockets instead of projectiles

The model is the same for now, but something interesting to try out for the Desolator is to convert it into rocket artillery.

The simple implementation is the following:
1.Hide the gun bone via scripts on the model
2.Increase size of model slightly
3.Remove thruster effects
4.Remove existing weapon
5.Add new weapon that fires 6 missiles from the 6 thruster bones - the missiles fly accross the map then arc down
6.Reuse the orbital missile projectile with a variation on it

A more advanced implementation could be:
Use a similar setup to the smaller rocket artillery - missiles fly across, tilt down and then accelerate really quickly, converting themselves into a new projectile like the rocket artillery.

Do whichever one is cooler. Or something along those lines!

This whole excercise is to solve the issue with it having a large time between individual muzzle shots, and also hitting mountains on the way, and also having a high muzzle velocity which we can control with the missile speed much easier.