Add encoder test:
- used for calibrating the length measurement by counting the steps
per meter
- enabled with #define ENCODER_TEST in config.hpp
- display1: enocder steps
- display2: converted length in meter
Distance conversion:
- defining STEPS_PER_METER instead of MEASURING_ROLL_DIAMETER in
config.hpp
- defining the steps per meter by issuing 3 test measurements with
4mm2 solar cable in the new encoder test mode
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