Prepare for v0.15 release

[jbeaurivage]

Summary

Prepare for v0.15 release. These are major breaking changes:

• Strip gpio::v1 and sercom::v1, promote gpio::v2 to gpio and sercom::v2 to sercom.
• Strip all the #[deprecated] items.
• Provide the necessary fixes to support those changes

Version numbering

Currently there are two competing opinions on whether we should version this next release as 0.15.0 or as 1.0.0. I'd like to hear your opinions on the matter!

Dependencies

This PR depends on #561, and ideally (but not mandatory) on #569.

Checklist

• CHANGELOG.md for the BSP or HAL updated
• All new or modified code is well documented, especially public items
• No new warnings or clippy suggestions have been introduced (see CI or check locally)

[bradleyharden]

Once we get rid of gpio::v1, what do you think about adding aliases to replace the Pa1 types?

type Pa1<M> = Pin<PA01, M>;

Does it hurt to have both PA01 as a PinId and Pa1 as a Pin alias? If not, should we be consistent with leading zeros? Are these aliases even worth it? Or does the bsp_pins! macro take care of most use cases?

[jbeaurivage]

Once we get rid of gpio::v1, what do you think about adding aliases to replace the Pa1 types?

type Pa1<M> = Pin<PA01, M>;

Does it hurt to have both PA01 as a PinId and Pa1 as a Pin alias? If not, should we be consistent with leading zeros? Are these aliases even worth it? Or does the bsp_pins! macro take care of most use cases?

@bradleyharden, if I'm being honest, I don't think adding more pin aliases is beneficial. Most people should be using the bsp_pins macro, and seeing as this release will definitely be breaking, it's a good time to only have one way of referring to GPIO pins. IMO, having multiple aliases to the same pin would probably lead to confusion. I remember when the gpio::v2 module came along, it took me a while to understand that Pa1 was now supposed to be called PA01.

[bradleyharden]

Sounds good. It was just an idea I had long ago, but it wasn't feasible then without breaking existing code.

[TDHolmes]

amazing 👏🏼 anything remaining to do here?

[jbeaurivage]

amazing 👏🏼 anything remaining to do here?

Nope I don't think so, I would merge #569 first though!

[TDHolmes]

merge conflicts now that #569 merged