Fix to work with mods that have faction side as a string instead of a number

Fixed bug where the destroy cache wasn't spawning.
Fixed bug in code that can cache enemy if needed.

. Feature: Destroy objective no longer exactly on marker
. Fix: 2 players needed more enemy
. Fix: Block arsenal loading (via 'load' button) of items not available in the arsenal
. Fix: Don't allow 'destroy' objective to be killed with a C4
. Fix: Death cam could follow flyby plane when players were alive
. Fix: heli flyby were deleted when objective captured even if they were overhead