Add BuildComplete property to Building and start initially locked.
Clean up Attack*.
Allow Attack* to control a subset of armaments.
Allow maps to define custom initial cargo and fix initial notification.
Move MuzzleFlash definition onto Armament.
Add AttackGarrisoned for allowing passengers to shoot outside. Fixes #4483.
Display fire ports in the combat debug overlay.
Add upgrade rules.
Port RA pillbox to new garrison system.
Fix retaliation against garrisoned actors.
Add changelog.