Clearer indication of unit being in AP mode

[ArnieO]

Is your feature request related to a problem? Please describe. Some customer express difficulties in seeing whether the unit is in AP mode. This is especially an issue on Pow-U, which needs to be powered by USB while in AP mode. It is then normally not connected to the meter, meaning that the blue part of the LED will be ON, and the yellow blinks will become white blinks when combined with the blue.

Describe the solution you'd like Next layout of Pow-U (layout v1.8.1) will have an option to disable the blue LED, as some customers are annoyed by the continuous blinking. It would then be a good idea to:

1. Disable the blue LED while the unit is in AP mode
2. Let the yellow light be steady ON, not just the current short yellow blinks.

I think yellow steady light while in AP mode could be implemented on all units, also today's design - unless there is a good technical reason for just providing the short blinks?