Refresh button on Connect radio page

[pfeerick]

A refresh button on the "Connect radio" stage of the DFU firmware flashing sequence would be great if possible, for when you have changed radios within a single session. As the same DFU VID:PID is detected, but Buddy seems to also be using the serial number, which changes from device to device. So you need to click "Add new device" and pick it again else the flash will fail.