update API and examples for egpio

[ChrisDick]

also fix units of Battery current.

Description

add new elements to the API for the the LS gpio and update examples. correct the units for the battery charge current from mA to A.

[ChrisDick]

I renamed it to match the name of the module. Do you think that matters? not sure it's wise changing the name in the sw, but we could while it's still in rc. I don't mind either way, happy to replace all occurrences in the docs if that makes more sense to keep consistency. Another solution is to make them all eGPIO except in the methods section and make that one egpio.ePin?

[npentrel]

@ChrisDick let's go with your suggestion and make them all eGPIO except in the methods section and make that one egpio.ePin in code formatting

[npentrel]

Merging for now