The default keymap for the Navi10

This keymap keeps a basic Navigation Cluster layout, but utilizes the Insert key as a FN/Tap key to access 2 layers.

Base Layer:
- Navigation Cluster (sans Insert Key)
Hold Insert -> Function Layer:
- Maps Volume Control on PgUp/PgDN, Pause/Scroll-Lock on Home/End (MacOS brightness), and Delete to Enter.
Tap Insert Once -> Media Layer (Tap again to leave):
- Has mappings for Audio control on MacOS using the arrow keys, PgUp/PgDn, and Delete.
- Lights up the Central 3mm indicator LED.