Added ability to add more map sources

olympus.json

@@ -14,6 +14,14 @@
             "provider": "https://srtm.fasma.org/{lat}{lng}.SRTMGL3S.hgt.zip",
             "username": null,
             "password": null
-        }
+        }, 
+		"additionalMaps": {
+			"DCS": {
+				"urlTemplate": "http://localhost:3000/resources/maps/dcs/{z}/{x}/{y}.png",
+				"minZoom": 8,
+				"maxZoom": 20,
+				"attribution": "Eagle Dynamics"
+			}
+		}
     }
 }