Survivor pack rework

Added survivor runner pack and duffel bag.
Removed varsize from all survivor packs.
Tweaked volume so all survivor packs are 25% bigger than non-survivor counterparts.
Recipies

Added survivor runner pack and duffel bag recipes
Tweaked existing survivor pack recipes
MOLLE pack nerf and survivor pack weight tweaks

MOLLE packs were obviously overpowered; they now have the same volume as a survivor backpack, 48.

Tweaked the weight of all the survivor packs so they follow a nice linear progression; larger packs are heavier, smaller packs are lighter.
Added spawns and tweaked existing survivor pack spawnrates
Minor survivor backpack/rucksack storage tweak

Originally got my math embarrassingly wrong, this fixes that.
Merge pull request #7813 from Izicata/patch-2

Survivor Pack Standardization