Add geolocation control

Author: cheeaun

app.css

@@ -87,6 +87,10 @@ body.modal #map {
   transform: translateY(-15%);
 }
 
+.mapboxgl-ctrl-top-right {
+  top: 55px;
+}
+
 #layers-button {
   outline: 0;
   border: 0;
@@ -432,6 +436,9 @@ body.modal #card{
 }
 
 @media (min-width: 768px) and (min-height: 600px) {
+  .mapboxgl-ctrl-top-right {
+    top: 0;
+  }
   #layers-button,
   #modal,
   #layers .close {

app.js

@@ -36,6 +36,12 @@ var map = new mapboxgl.Map({
   attributionControl: false, // Attribution is inside Layers modal
 });
 map.touchZoomRotate.disableRotation();
+map.addControl(new mapboxgl.GeolocateControl({
+  positionOptions: {
+    enableHighAccuracy: true,
+  },
+  trackUserLocation: true,
+}));
 
 var maxBoundsLike = [
   [ 103.6016626883025, 1.233357600011331 ], // sw