Update 0.6.8.57

• Replaced the 500 kg Number 50 Model 2 bomb of the Kikka with a 800 kg Number 80 Model 1 bomb.
  
• Adjusted the weapons of the soldiers used by BR III AI commanders, except in Flametrooper squads.
  
• Adjusted the weapons of the soldiers used by BR V AI commanders.
  
• Adjusted the premium squads used by BR III and V AI commanders.