RNA: move cursor into own struct

Without this it's impractical to subscribe to any change to the cursor.

Fixes T61969 by having gizmos update on any change to the cursor.

release/scripts/modules/bpy_extras/object_utils.py

@@ -61,7 +61,7 @@ def add_object_align_init(context, operator):
     if operator and properties.is_property_set("location"):
         location = Matrix.Translation(Vector(properties.location))
     else:
-        location = Matrix.Translation(context.scene.cursor_location)
+        location = Matrix.Translation(context.scene.cursor.location)
 
         if operator:
             properties.location = location.to_translation()