ENH: VPAW Visualize and `qt.QSettings`

[Leengit]

The VPAW Model module was recently updated to store form field values via qt.QSettings() so that the form field values are application-wide, not scene-specific, and will be re-populated when the VPAW application is restarted. Consider doing the same for one or more form fields in the VPAW Visualize module. Also, for the form field(s) that are duplicated between the two modules (e.g., the data directory) consider whether they should be forced to be equal vs. stored and re-populated independently.

[ebrahimebrahim]

Agreed -- the same should be done for VPAWVisualize.