Camera shake and other changes

Updates:

- Camera shake added to Orbital Strike. It makes the whole thing significantly more menacing!

- Turrets, mines, refineries and factories have increasing build cost. The more you build from the same type, the more expensive the next one will be. All 7 turrets share this, so it does not matter which turret you build, the next one will be more expensive. Same for mines and refineries.

- Mines and refineries give a bit more mineral and resource. This is to compensate for the increasing build cost.