* proof of principle, a DS18B20 is read and its value is transferred via MQTT, also discovery message works
* added names for ext sensors
* bugfix for names: there was a problem with the topics & added SHT21 support
* catch exceptions if a problem during readout occurs, shrink comments in config-file
* include ext_sensors in README file
* work in progress
* bugfix, also for ID of ds18b20 sensor
* Revert "bugfix, also for ID of ds18b20 sensor"
This reverts commit 1353b840b0b6142670ec59438db4b33fab764b8e.
file was intended for another branch
* Revert "work in progress"
This reverts commit b3e884f79f5356b79f64931cb4d45a150bfce2c7.
these changes were intended for another branch
* bugfix for ID of ds18b20 sensor
