* Adds Audio Keycodes to both the feature page and master list
* Re-orders the keycode list, so it's alphabetical (mostly)
* Add additional (missing) sections to the keycode list
* Add and update links in the keycode page
* Add and reorder links in sidebar's keycode section
* Clean up SEND_STRING keycodes and add media keys
* Remove stray define
* Add missing SEND_STRING keycodes for completeness
Also, add KC_EJCT to the keycode references
* Macro for a momentary layer switch with mods
Passes through to the existing ACTION_LAYER_MODS macro, albeit with more
limited options due to lack of space in the quantum_keycodes enum.
* Add documentation for LM layer-mod macro
* Clean up Tap Toggle documentation