Update armor.json

Adds dusters. They're modeled after the trenchcoat items but also cover the legs. Their volume, weight, and components needed to craft are 35% higher than trenchcoats.
Update recipe_armor.json

The duster recipes. Have a 35% higher component requirement than trenchcoats.
Update item_groups.json

Simply adds duster spawn chances to the same places trenchcoats spawn, and at the same spawn rates.
Update armor.json

Adds dusters.

Removed water/rain proof from cloth dusters.
Update item_groups.json

Halved trenchcoat and duster spawns, to make up for the addition of the dusters.
Merge pull request #10172 from Dragoonseal/master

Adds dusters