Move encoder selection to encoding settings

This will automatically update profiles to the new encoder selection
according to the old setting resolution, i.e. UseQSV && UseNVENC results
in QSV being selected.

This should free up some space to allow more encoder troubleshooting and
diagnostics in the settings window (relevant QSV changes coming soon ...)

Also hopefully made supported encoder settings a bit more clear by
disabling more settings if the selected encoder doesn't support them