Connect to scanner

Connect the application to the registered scanner

Required

• The variable persistentValues/SCANNER_WIFI needs to exist, and contain the wifi name of the local scanner.

Effects

• Establishes scanner-connection

Function exits

• On success: The scanner could be reached and validated
• On battery error: The scanner's battery voltage is lower than the given threshold
• On scanner error: The connection could not be established for another reason
• On wrong scanner error: The paired and the currently connected scanner are not the same
• On wifi error: The device is not connected to the scanner