nice!nano v2 docs suggestions

[SethMilliken]

Some issues with the v2 pinout schematic:

1. This pinout image is the only place that "charge boost" is documented, which means it's not searchable. The how do you charge the nice!nano faq might be a good spot to include this info, too.
2. The external vcc cutoff description in this nice!nano v2 pinout image references P0.13, but that pin is not labeled in the image (presumably it is an alias for the 3.3V pin, which the v1 pinout image does show).
3. That v2 cutoff description says that when it is set low it shuts off power; but the v1 image and text clarification say that it is cut off when set high. It might be worth explicitly calling out that this is a difference between v1 and v2.
4. It might be worth listing bullet points for the differences between v1 and v2 somewhere (it looks like splitkb.com has collected them).
5. It might be worth documenting the status LEDs. From your pinned #nice-nano Discord message:

Blue: Status LED, programmable by firmware and the bootloader uses it. Double flash happens on reset of the nano. Slow pulse means the bootloader is connected to the host computer. Fast pulse means it's waiting for a USB connection to the host device or it could be writing to the flash if you just dragged a uf2 file over.
Orange: Only true for v1 Blinking means no battery is connected usually, solid means that the battery is charging, off means the battery is fully charged or you're not charging.