* debug: heap fragmentation stat

* Rework method detection

- return check integral type as a result of detection instead of method type
- type-tagging instead of enable_if

* fix alias

* typo

* only need one bool_type instance

* Move heap debug into HeapStats header

- don't show fragmentation stats on the first call
- prettify fragmentation display
- pack function params into helper struct
- naming

* pass external flag instead

* add missing prototypes

* MQTT: config change detection
* Reload settings when config json is uploaded
* Apply only new settings
* Finish config early when not enabled
* Reuse existing buffers from getSetting String using std::move

- store system crash counter and reset reason in rtcmem instead of eeprom
- store relay state mask in rtc in addition to the eeprom
- store relay state in eeprom only when boot mode requires it
- simplify relay state mask calculation / reading using std::bitset
- light state save and restore
- energy total save and restore

- remove optional RFRAW_SUPPORT
- enable module when RF_SUPPORT=1, optionally enable RCSwitch
- reorder ifdef checks to treat RFB_DIRECT and old RF_SUPPORT the same
- rename RF_PIN to RFB_RX_PIN
- depend on RF_SUPPORT instead of ITEAD_SONOFF_RFBRIDGE
- runtime TX & RX PIN setting

* Call delay() after callbacks
* Use safer loop delay value

* Merge RF and RFBridge code

* Keep rfbridge.ino filename

* Corrected #if checks

* Make RF_DEBOUNCE and RF_LEARN_TIMEOUT configurable

* Fix compile warnings with platform_latest