Add Nanhai route scenario

data/campaign/campaign.json

@@ -303,6 +303,11 @@
       "id": "060_southern_holdouts",
       "title": "Southern Holdouts",
       "path": "res://data/scenarios/060_southern_holdouts.json"
+    },
+    {
+      "id": "061_nanhai_route",
+      "title": "Nanhai Route",
+      "path": "res://data/scenarios/061_nanhai_route.json"
     }
   ]
 }