Add submission # 5857

#5857

Author: ArduinoBot

registry.txt

@@ -7850,3 +7850,4 @@ https://github.com/totemmaker/TotemRoboboard.git|Contributed|Totem Roboboard
 https://github.com/Neurotech-Hub/Hublink-Node.git|Contributed|Hublink-Node
 https://github.com/Neurotech-Hub/Hublink-BEAM.git|Contributed|Hublink BEAM
 https://github.com/DigitalFuturesOCADU/TinyFilmFestival.git|Contributed|TinyFilmFestival
+https://github.com/sensebox/rg15-arduino-lib.git|Contributed|RG15-Arduino