Clear heli Inventories of all but UAV

[martinco]

Originally reported by: Martin Collins

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• still require a way of paradrop
• from helis an action to drop which is available under the following scenarios
  • pilot action to green or red light drops
  • pilot is dead
  • heli has lost atrq or rotor
  • engine failure is ok due to autorotate and that provides enough opportunity to green
• Pilot action can be done a few k from lz with verbal command to jump, it's there just to avoid people jumping for the sake of it
• players keep their backpack

[martinco]

Original comment by Martin Collins:

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Fix #228: Trim Heli Inventories, Allow Pilots to greenlight paradrops