Favorite Mounts Enhanced

## Overview
This is a MAJOR update. I've marked it as a beta because there are still some minor bugs (mostly with layering) and some commands may be broken.

## Changes:
- Minimap icon that opens the 'Summon Mount' panel
- Summon Mount panel for summoning mounts from your lists: "Random" = /mountrandom, "Cycled" = /mountordered
- List Management panel for creating lists, deleting lists, adding mounts to lists and deleting mounts from lists
- Add Mounts panel for adding mounts (opened by the "Add Mounts" button
    - The list in this panel is currently not sorted

## Known Issues
- Panel layering is very messed up when they overlap
- Escape closes all panels. This may not be desirable functionality
- You may encounter errors when pressing certain buttons while the panels are in certain states. I believe I missed some corner cases in my testing