* test: etharp_gratuitous

* proper checks before calling etharp_gratuitous, move includes

* disable at runtime

* ms values

* reload

* debug

* reword

* filter by ifnum instead of checking for AP mode

* drop station_if check

2.3.0/lwip1 builds netif->num increments on for each sta or ap
lwip2 keeps those constant, but that seems like a implementation detail
might break in the future anyways...

* Light: proper printf format for HSV, use lround

* core: warn about map() and 2.3.0, type-strict constrain()

* use generic format

* value already has brightness

* MQTT rewrite with SSL fixes

- Added Arduino MQTT library support (actively maintained)
- Added support for BearSSL (core >= 2.5)
- BearSSL validation: insecure, fingerprinting and CA validation
- AxTLS validation: insecure and fingerprinting
- Support MFLN in order to reduce heap usage

* Better header incl, fix building w/ no NTP_SUPPORT

* Clean up code, use DEBUG_MSG_P

* Fix compile error

* Core 2.6.0+ fixes

* fix env -> config, run travis04 job

* don't duplicate free heap in frag data, use single stats struct

* fix dtostrf warnings, bump buffer sizes

* ...and even less words for fragmentation stat

- add httpupdate ota impelementation
- move async ota into a separate module
- support bearssl & axtls through wificlientsecure
- allow to disable arduino ide ota module

https://github.com/xoseperez/espurna/issues/1839#issuecomment-518248474

* Telnet rewrite, no longer using ESPAsyncTCP

* Support two telnet server implementations

* Clean up diff

* Update types, no free() calls, cleanup

* Use std::unique_ptr

* Fix nullptr checks

* Fix double log with async server

* Common new connection method

* use same connected() check as sync variant

* fixup! use same connected() check as sync variant

* Fix compile issue, close connection in case of timeout and when max connections reached

* Use AyncsClient* in function call

* Allow overriding telnet port + max clients

* Do not allocate 512 bytes by default

* Use TERMINAL_BUFFER_SIZE

* Make compilation more flexible allowing to define in custom.h your own variation to devices and define four wifi networks

* Implement suggestion from Max Prokhorov, it's simpler and cleaner

* Change a #elif by #else

* Move ESPurna Core comment

* Update encoder

- import modified Encoder library
- customize minimum delta value

* minimum delta in header config

* fixup! minimum delta in header config

* fix dead code, actually use interrupts

* move static class methods to normal funcs, apply namespace

* drop hardcoded register use

- use peripheral api (see cores/esp8266/esp8266_peri.h)
- remove bitmask and register struct members

* add a note about changes

* fixup! add a note about changes

Allow defining custom device name for alexa integration, other than hostname.
Still uses hostname as a fallback.

- 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

1. Add thermostat to the espurna_modules in progmem.h
2. Add thermostat to webui, gulp, html, js.
3. in general.h MQTT_USE_JSON returned to 0 by default and 1 if thermostat enabled.

- Heartbeat mode and interval configuration added to WebUI ADMIN page
- New option HEARTBEAT_REPEAT_STATUS: on device startup full heartbeat information and after HEARTBEAT_INTERVAL only STATUS report.
- Enhanced first heartbeat message - on device startup it will send heartbeat after ntpSynced will be true to get device time.

P.S. Code is tested. Web part is not compiled, and not tested. I hope it will work :)

* 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

* Telnet auth depends on setting

* use same define suffix as WS_

* add to web

* no initial passwd for core

* allow override of WEB_REMOTE_DOMAIN

* allow override of HOMEASSISTANT_ENABLED and _PREFIX

fix 30285b3

* fix webui regexp and input length limits
* explain requirements in webui and headers