clarify that lighthouse IP should be nebula range (#196)

examples/config.yml

@@ -36,6 +36,7 @@ lighthouse:
   interval: 60
   # hosts is a list of lighthouse hosts this node should report to and query from
   # IMPORTANT: THIS SHOULD BE EMPTY ON LIGHTHOUSE NODES
+  # IMPORTANT2: THIS SHOULD BE LIGHTHOUSES' NEBULA IPs, NOT LIGHTHOUSES' REAL ROUTABLE IPs
   hosts:
     - "192.168.100.1"