Catalog tree selectedItem may not work as expected

A layer that is preselected in the catalog tree configuration won't be actually selected and displayed on the map if its ancestors are not preselected. It will be added to the map when the user expands its parent nodes in the tree.

It seems to me that the issue is related to our use of [`ng-if`](https://github.com/geoadmin/mf-geoadmin3/blob/master/src/components/catalogtree/partials/catalogitem.html#L20) in the catalog item partial.