Use leaflet.restoreview.js plugin to save and restore last user's map position between sessions (#48)

bower.json

@@ -20,7 +20,8 @@
     "Leaflet.EasyButton": "*",
     "bootbox": "~4.4.0",
     "seiyria-bootstrap-slider": "~4.8.1",
-    "url-search-params": "~0.5.0"
+    "url-search-params": "~0.5.0",
+    "Leaflet.RestoreView": "makinacorpus/Leaflet.RestoreView#master"
   },
   "overrides": {
     "leaflet": {
@@ -79,6 +80,9 @@
     },
     "url-search-params": {
       "main": "build/url-search-params.js"
+    },
+    "Leaflet.RestoreView": {
+      "main": "leaflet.restoreview.js"
     }
   },
   "resolutions": {

js/index.js

@@ -74,10 +74,11 @@
         });
 
         map = new L.Map('map', {
-            center: new L.LatLng(50.99, 9.86), 
-            zoom: 6,
             worldCopyJump: true
         });
+        if (!map.restoreView()) {
+          map.setView([50.99, 9.86], 6);
+        }
         map.attributionControl.addAttribution(
                 '<a href="http://brouter.de/brouter" target="_blank">BRouter</a> &copy; Arndt Brenschede, '
                 + 'routing + map data &copy; <a target="_blank" href="http://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors '