Larger ships/emplacements (for now...may decrease one or the other later)

Also added origin-x and origin-y attributes for emplacements to set the point about which they rotate
More precise projectile firing

- Added JsonEmplacementProjectile glue class to link emplacements and projectile source locations
- Emplacements can now have multiple projectiles fired at once
Implemented hull and shield regen
Added min/max angles for ship emplacements (not actually constrained yet)
Implemented constraining angles in emplacement

- still need to fix AI such that the emplacements rotate smartly