add: add unversioned files

lib/amap_marker.dart

@@ -0,0 +1,17 @@
+
+class AmapMarker {
+  double lat;
+  double lon;
+  Map<String, dynamic> extras;
+
+  AmapMarker(this.lat, this.lon, this.extras);
+
+  Map toMap() {
+    Map map = {
+      "lat": lat,
+      "lon": lon
+    };
+    map.addAll(extras);
+    return map;
+  }
+}