Feature Request: remote control command for IO restart

[akhepcat]

Sometimes linux USB gets wonky, and the SDR device will disconnect and reconnect

When this happens, gqrx stops decoding - as expected - but there's no way to restart things without manual gui intervention (UI -> IO devices -> rescan)

having a remote-control option available to call CIoConfig.onScanButtonClicked() would be very useful, as a watchdog could monitor dbus (or syslog/dmsg) for the input device dropping and reconnecting and then send the requisite rescan command over the remote control interface.

my c++ isn't strong enough to figure out how to emit that signal from a separate namespace, at least not in the 20 different attempts i tried.