suggestion: vim nav: use tap-hold to lock or not numpad/funpad layers

[bouttier]

numpad & funpad: quick tap lock the layer while long tap does not

This allows to quickly input number or press Fn key without locking these layers.

[fnuttens]

Great idea! I’ll start using this in my personal config right away 🙂

[bouttier]

Add at least one @std action in the funpad layer to escape the layer-switch.

Ah yes, I stayed in the other PR #49, I will add it to this one!