Add ignf aerial pictures and base map (#636)

* add ignf layers

* removes ignf-boundaries

* Assign France bbox to IGNF layers

but don't restrict bounds because world wide coverage in lower zooms

Co-authored-by: Sylvain Lafay <sylvain.lafay@gmail.fr>
Co-authored-by: Norbert Renner <norbert.renner@gmx.de>

layers/config/tree.js

@@ -47,6 +47,12 @@ BR.confLayers.tree = {
                 ]
             },
             'topplus-open',
+            {
+                'FR': [
+                    'ignf-aerial',
+                    'ignf-map',
+                ]
+            },
             {
                 'IL': [
                     'Israel_Hiking',