- Add ::Released button event to be used specifically with switches, opposite of ::Pressed
- Always use default state for switches instead of ignoring it and using current pin reading as value. This allows us to boot with the switch held in the opposite state and trigger the correct event immediately
(meaning, switches now depend on the BUTTON_DEFAULT_HIGH presence to detect the default position)
- BREAKING: Fixup hardware.h. Any custom board needs manual changes.
- BREAKING: Rework MQTT button messages to send text from debug messages instead of numeric code

resolve #2310

* wip

* cleanup buttons-through-serial code, remove hw mention from button module

* remove wip

* implement mqtt settings

* fixup struct members, dual no longer allocates debouncer

* add missing debounceevent lib

* fix missing event_handler, update names

* fix namespace

* drop lib

* fix int<->bool comparison

* Move gpio16 handling from DigitalPin to EventHandler

* Cleanup debounceevent headers

* Don't expect system headers to be included

* re 70b54c489f - no allocation, for real

* Adjust settings names

* dont retain by default

* unused

* typo

* Fix length type (ref 6017ad9474)

* Move pin class outside of debounce lib, lowercase ns

* move event handling inside of button_t

* refactor config. ..._MODE -> _CONFIG, ..._MODE_... -> ..._ACTION_...

* fix test

* naming

* move indexed value to header

* refactor actions into direct opts

* fix webui, fix buttons not respecting old user setting

* change button config format from bitmask to a struct, adjust settings conversion

* proxy some more header defautls, fix web kv

* gpiopin

* adjust webui func to support every setting

* clarify single-return event->string

* fix dual setting

* fix dual packet condition, de-duplicate funcs

* fix bogus warning