P: "Detecting camera" dialog during tethering should be less obtrusive

When tethering it's common to change lenses or batteries. 
This causes the "detecting camera" dialog to appear directly in the middle of the screen, and it blocks the viewer. 
 My clients often almost reflexively hit the cancel button, meaning I need to manually restart the tether session. 

Capture One handles informing the user of the tether status a lot more gracefully. The current implementation isn't really appropriate when clients or other team members may be monitoring the shoot via the tether session.