[Badger 2040] include halt() in documentation?

[bucketfish]

while looking through some github repos of badger code, i came across the function halt(), which doesn't seem to be in the documentation. perhaps it should be, in somewhere like the updating the display section? hopefully there isn't a reason for it to not be there that i've missed :'

thanks!

[Gadgetoid]

Badger 2040 and Badger 2040 W now live here: https://github.com/pimoroni/badger2040/

I don't think we have covered this in the docs, so I'm going to close the issue here but make a note to check.