The asyncio module now has much better CPython compatibility and
deserves to be just called "asyncio".
This will avoid people having to write `from uasyncio import asyncio`.
Renames all files, and updates port manifests to use the new path. Also
renames the built-in _uasyncio to _asyncio.
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Including the uasyncio scripts and the drivers for DHT, DS18x20 and
onewire. The uasyncio scripts need about 8k of flash and are not included
for the SAMD21 boards by default.