Move routing API endpoint addresses to config file

app/assets/javascripts/index/directions/graphhopper.js

@@ -21,7 +21,7 @@ function GraphHopperEngine(id, vehicleType) {
       // GraphHopper Directions API documentation
       // https://github.com/graphhopper/directions-api/blob/master/docs-routing.md
       return $.ajax({
-        url: document.location.protocol + "//graphhopper.com/api/1/route",
+        url: document.location.protocol + OSM.GRAPHHOPPER_URL,
         data: {
           vehicle: vehicleType,
           locale: I18n.currentLocale(),

app/assets/javascripts/index/directions/mapquest.js

@@ -36,7 +36,7 @@ function MapQuestEngine(id, routeType) {
       var to = points[points.length - 1];
 
       return $.ajax({
-        url: document.location.protocol + "//open.mapquestapi.com/directions/v2/route",
+        url: document.location.protocol + OSM.MAPQUEST_DIRECTIONS_URL,
         data: {
           key: OSM.MAPQUEST_KEY,
           from: from.lat + "," + from.lng,

app/assets/javascripts/index/directions/mapzen.js

@@ -39,7 +39,7 @@ function MapzenEngine(id, costing) {
 
     getRoute: function (points, callback) {
       return $.ajax({
-        url: document.location.protocol + "//valhalla.mapzen.com/route",
+        url: document.location.protocol + OSM.MAPZEN_VALHALLA_URL,
         data: {
           api_key: OSM.MAPZEN_VALHALLA_KEY,
           json: JSON.stringify({

app/assets/javascripts/index/directions/osrm.js

@@ -51,7 +51,7 @@ function OSRMEngine() {
       }
 
       return $.ajax({
-        url: document.location.protocol + "//router.project-osrm.org/viaroute",
+        url: document.location.protocol + OSM.OSRM_URL,
         data: params,
         dataType: "json",
         success: function (data) {