Policy of adding and removing devices from the list

When the proper advertising packet is received the first time and a device which is unknown yet, the device is added to the list and get it's own index number. This number is used for identification on MODBUS. Unfortunaltely, this index value cannot be changed directly, numbers are assigned consecutively when very first packet arrive. Due to unknown time of advertising interval, removing devices is manual - pushing button (BUTTON1 on PCA10001) cleans the whole list and enumeration starts again.