Another type of payload from the IRremoteESP8266, intended to be used
with HVAC devices. Also add a bunch of comments in regards to IRac.h
More tweaks to the internal StringView and ParseResult, make
sure the implementation closely follows the STL alternatives.
More configuration options for the:
- Transmitter, support INPUT_PULLUP
- Receiver, allow to set signal inversion and modulation.
Correctly implement buffer size setting.
- MQTT topics, allow to override both in and out
Also fix the 'simple' parser HEX range, accepting 8byte payloads (16chars)
and allowing lowercase inputs.