Minor update, a clever ergonomic modification and various bugfixes !

Ergonomy

• Planet opacity changes once the player has used all the associated actions.
  

Bugfix

• Missile ammo now decreases after destroying an asteroid field.
  
• System failure repair now repairs 4 items again on habitable planets (instead of 2)
  
• Unprovoked neutral NPC no longer attacks the player when the player attacks an enemy.
  
• Neutral NPC shoots back again after the player uses multi-target on him
  
• Multitarget no longer works when the player doesn't have enough ammo
  
• It's no longer possible to use a higher level attack than the ammo level allows
  
• Turn count no longer glitches when neutral NPCs are EMP paralysed
  
• Missile gauge corrected to take into account only valid targets during multitargeting.
  
• Corrected instances where it wasn't possible to use the missile launcher when only one missile was left.
  
• Corrected instances where it wasn't possible to use the laser when only one thorium unit was left.