Add support for the ESP8266 deep sleep and required change for DS1820 sensor used in my project.
Allow defining DS1820_RESOLUTION and DS1820_INTERVAL_SEC in ENVIRON without editing config file.
Allow DTimeBetweenReadingmq2 Env. MACRO change without editing source config file.
Added some an example ENVIRONMENTS
Add ESP8266_DEEP_SLEEP_IN_US to nodemcuv2-all-test
* Detect when sensor isn't available or read fails
* Add temperature conversion macros
* Add 'tempc' & 'tempf' keys to published values
* Unique Values for HA Discovery
* Remove degree symbol from temp sensors
Co-authored-by: Jonathan Michael Wells <jonathan-wells@oist.jp>