#2430 API setter to toggle and repaint (SHOW_CONNECTORS_PROPERTY)

[Luigi Kang]

I'd like to request a proxy map API boolean to toggle the show/hide connectors feature, to emulate the main program's code.
MapView.showConnectors = ResourceController.getResourceController().getBooleanProperty(SHOW_CONNECTORS_PROPERTY); mapView.repaint();

I believe the ability to quickly toggle show/hide connectors would be useful for presentation as well. Thanks for considering.