Put the reaver + shuttle in different squads.

- The reavers and shuttle now show up in a different squad (harass squad)
- They leave towards the enemy together without waiting for the other
  squads
- ISSUE: Halfway through the motion of the shuttle, it appears that the
  shuttle loses the "harass opponent" command (the box that shows which
  squad they are in).
- ISSUE: Sometimes the shuttle doesn't drop the reaver.