add belgium topo layer

website/src/locales/en.json

@@ -133,6 +133,7 @@
             "overlays": "Overlays",
             "world": "World",
             "countries": "Countries",
+            "belgium": "Belgium",
             "bulgaria": "Bulgaria",
             "finland": "Finland",
             "france": "France",
@@ -153,6 +154,7 @@
             "linzTopo": "LINZ Topo50",
             "swisstopo": "swisstopo",
             "swisstopoSatellite": "swisstopo Satellite",
+            "ignBe": "IGN Topo",
             "ignFrPlan": "IGN Plan",
             "ignFrScan25": "IGN SCAN25",
             "ignFrSatellite": "IGN Satellite",