Discovery Update

[effelle]

Description:

Changelog:

• Add a new definition, DEEPSLEEP_LWT_HA_DISCOVERY, to enable LWT topic and its payloads for read-only sensors and binary_sensors on HAss Discovery. When commented out (default) all read-only sensors and binary_sensors won't be shown as OFFLINE on Home Assistant when the device is DeepSleeping
  NOTE: This is only for read-only sensors and binary_sensors, relays/lights and status sensor will be shown as OFFLINE);
• Add support for Tuya and Sonoff MCU relays/lights;
• Some more sensors added.

Related issue (if applicable): fixes #8655

Checklist:

• The pull request is done against the latest dev branch
• Only relevant files were touched
• Only one feature/fix was added per PR.
• The code change is tested and works on core ESP8266 V.2.7.1
• The code change is tested and works on core ESP32 V.1.12.2
• I accept the CLA.

NOTE: The code change must pass CI tests. Your PR cannot be merged unless tests pass