In addition to exposing additional configuration settings, it now also
provides access to the wifi station power-saving control.
Documentation updated, and wifi.sta.getconfig() has been documented. Not
sure why that wasn't already the case.
Changes have been kept to a minimum, but a serious chunk of work was
needed to move from 8266isms to IDFisms.
Some things got refactored into components/lua/common, in particular
the LFS location awareness.
As part of this work I also evicted our partition table manipulation
code, as with the current IDF it kept breaking checksums and rendering
things unbootable, which is the opposite of helpful (which was the
original intent behind it).
The uart module got relocated from base_nodemcu to the modules component
properly, after I worked out how to force its inclusion using Kconfig alone.
Only compile-tested so far.
Of note is that the WiFi auto-connect (flag) functionality has been removed
from the IDF, and as a follow-on so has the "auto" field in the wifi config.
On the Ethernet side, support for the TLK110 PHY seems to have been removed,
but on the other hand there is now new support for several others.