Save speed of Scanning

[klues]

Problem
in the "Simple mode" there is the possibility to start scanning for users with a one switch interface. Its possible to set the scanning speed by a range input, however this setting is not saved.

Solution
Save setting for scanning speed and re-apply it if AsTeRICS Ergo starts again. In addition it should be saved if scanning is on or off, so that it starts again automatically on restart (if on).