* remove lwip-v1.4 specific code
* ditto
* ditto
* fix ip4_addr definition
* CI: change debug builds to use IPv6, remove regular IPv6 builds
* ditto
* split pio CI in four (because they last twice the time of the other builds)
* remove option from pio
* remove lwIP-1.4 from doc
* restore pio CI splitting
* fix CI debug6 script
* ditto
* Add boards filter support - allows for the creation of an abridged boards.txt.
Add some of the ITEAD Sonoff boards to boards.txt.py.
Minor reorder of presentation of board menu items, mainly grouped
board Model and module selection to the top.
* Corrected, I think, LED_BUILTIN vs BUILTIN_LED??
* Updated boards.txt
* Added support for DOIT ESP-Mx DevKit (ESP8285) board.
Adjusted wording and fixed side bar formating issue on the
Sonoff description. Also, removed resetmethod menu
and assigned resetmethod of none.