leaflet 7.x-1.0-beta3

Changes since 7.x-1.0-beta2:

• Add a Views display setting allowing you to hide a map if there are no results or show an empty map.
• Add hook_leaflet_views_alter_points_data
• Cleaned up views pop-up attachment, and added the title field to the data array so it can be re-used elsewhere
• Triggering a jquery event when a new feature gets added to the map. This allows anyone else to register using $(document).bind('leaflet.feature', function(e, lFeature, feature) { }});
• Allowing other modules to bind event handlers to the leaflet.map event broadcasted using jQuery's trigger method
• #1903444 by onelittleant: fix JS error related to hidden fields
• Fix API description, as per #1912496