refactor: export install as named export for tree shaking (#940)

ktsn · yyx990803 · commit fb06cc4aeffc · 2017-09-12T11:54:50.000-04:00
diff --git a/src/index.esm.js b/src/index.esm.js
@@ -14,6 +14,7 @@ export default {
 
 export {
   Store,
+  install,
   mapState,
   mapMutations,
   mapGetters,
