Changes all coats and jackets with buttons to be subtypes of /obj/item/clothing/suit/storage/toggle and changes the way the toggle verb functions to be dependent on defined icon states within the item

This means that adding a new type of jacket that toggles will be much easier, as instead of having to duplicate the entire old function and hardcode icon states for open and closed, you can just add in a new item as a subtype of suit/storage/toggle and define the icon states there. Also makes on-the-fly modifying of icons easier.
Adds in new clothing items from Baystation12's dev branch.

Leather jacket, with and without NT logo.
Brown leather jacket, with and without NT logo.
Gray hoodie (which also increases resistance to cold).
Bad wording change to slightly less bad wording.
Merge pull request #6 from MagmaRam/newcoat

Reworks buttoning for coats and adds new exterior suit items from BS12's dev branch