Plague 3.07 - mainly bug killing

• made zombies and survivors panic and flee when on fire
• grenade sprint throw “bug” removed
  
• make incendiary the default grenade
  
• fixed control bug where player would stop receiving input because input was not “fresh”
  
• changed bullet physics so that embedded bullets actually embed all the time
  
• reduced laser_pule_temp from 5 to 50 (necessary because embed bug fixed)
  
• added 2000 burn damage to laser pulses
• fixed text – I dropped some brackets when rewriting it...
  
• reduced num_zombies to 60 again for speed
  
• reduced zombie sight radius to 8 for speed
• reduced soldier sight radius to 14 for speed