ce0db0d329
This consolidates the UI code for NDOF input settings, making all settings accessible from the preferences. This works around an issue where the Space Navigator's "Menu" button doesn't trigger the settings menu in Blender. I also took the opportunity to redo the UI layout. Note: Separate commit for 2.83 because UI layouts features have diverged. Differential Revision: https://developer.blender.org/D7806