Bastion Turret

New
- Overwatch Link: a Hub Connector with a camera and fire control, made at the Module Workstation. Shift + right-click a Hub Interface to link it, put it in a turret's Connector slot, then on the hub's map shift-click that turret and press Take control.
- You see from the turret (a raised third-person view, F5 for a sight over the barrel), aim with the mouse and fire with attack. Manual aim ignores turn speed; a controlled turret reaches 1.5x farther (server config overwatchRangeMultiplier) and fires even when switched off. Scroll to zoom, arrow keys to switch turret, sneak to leave; taking damage also ends it.
- The camera HUD shows HP, ammo or FE, heat, charge and reload, and marks where the shot really lands. Mortar shots show their arc and landing ring. Tesla Coils and Repulsor Domes can be watched.
- Jade and the turret GUI show who is controlling a turret.

Changes
- Right-clicking a Hub Interface opens its screen whatever you hold; shift + right-click links a Hub Connector or places a block.
- Gun, Shotgun and Sniper bullets are amber like the Machine Gun's (their sights and holograms keep their colours); the Shotgun's spent shells are brass.

Fixes
- A Machine Gun switched off mid-burst kept its barrels spinning.

Note
- Clients need this version to join a 0.3.0 server (new network packets).