23-os2l (#32)

Implements the OS2L feature (tested with Virtual DJ).
Graphics improvements.

Reviewed-on: #32

project.go

@@ -136,7 +136,7 @@ func (a *App) OpenProject(projectInfo ProjectInfo) error {
 		}
 		_, err = hostFinder.RegisterPeripheral(a.ctx, value)
 		if err != nil {
-			return fmt.Errorf("unable to register the peripheral S/N '%s'", key)
+			return fmt.Errorf("unable to register the peripheral S/N '%s': %w", key, err)
 		}
 	}
 	return nil