Harmonize bsp api with an eye towards clean docs

[jacobrosenthal]

Just to start a discussion around what our bsp api should look like.

Most of us are using inherited a pattern that splashes the hal into the main export that ends up looking like this
https://docs.rs/pygamer/0.6.0/pygamer/

Recently merged bsps clearly rethought that. Take a look at
https://docs.rs/wio_terminal/0.2.0/wio_terminal/

I presume wed like to be harmonized. And presumably wed all like our docs to look nice.

These were the (breaking) changes I made to the pygamer and edgebadge just to generally clean them up, and ended up converging to the wio terminal style.

Though Id prefer to match whatever we all decide.

[twitchyliquid64]

Sorry for the inconsistent style with the wio_terminal - it wasnt my intention to buck the trend, but I do think consistency is ideal.

I can also tackle updating some of the other BSPs if that would help? I have hardware for the itsybitsy's.

[jessebraham]

Just regarding the wio_terminal crate, that was originally in a separate repository which I created which was later merged in here. The API differences are largely my doing, but I honestly don't have a strong preference on how to do things as long as it's straight-forward.