Make items draggable in the loadout edit drawer.

[ryan-rushton]

Overview

This PR makes items drag and droppable in the edit loadout drawer.

I realise that we also have the double click functionality but I imagine most of our users expect to be able to drag things as it is the default way to move items in the app. TBH I didn't know I could double click until I made this change.

There is probably more refactoring I could do around some of these components too but I might leave it to this to ensure the change doesn't get too large.

https://user-images.githubusercontent.com/7344652/187911583-763b9a3b-377b-4684-8ade-a0555e1a7827.mov