Tidy up the MixDeviceWidget context menu generation
Let MixDeviceWidget::contextMenuEvent() handle the initial creation and eventual showing of the menu. Rename the pure virtual showContextMenu() to createContextMenu() and have it only add the control-specific actions to the menu. Remove the "Hide" control action and MixDeviceWidget::setDisabled(). The action was only defined for a MDWEnum and was not accessible in the GUI. The same effect can be achieved using "Configure Channels".
Showing with 38 additions and 62 deletions