PSA: Future development

[MabezDev]

Future development will now be focused on the multi-chip hal, esp-hal. We now have official SVD's from Espressif, and they differ slightly to the hacked up variant we used for this HAL.

There is still plenty of useful stuff here that will need to be ported over, so if you want to help please consider taking a driver from this crate and adapting it to fit into the new multi-chip hal.