Use es6-map as native Map polyfill

package.json

@@ -10,6 +10,7 @@
     "debug": "^2.2.0",
     "detect-browser": "^1.3.3",
     "direction": "^0.1.5",
+    "es6-map": "^0.1.4",
     "esrever": "^0.2.0",
     "get-window": "^1.1.1",
     "immutable": "^3.8.1",

src/utils/memoize.js

@@ -1,5 +1,4 @@
-/* global Map */
-
+import Map from 'es6-map'
 import IS_DEV from '../constants/is-dev'
 
 /**