feature(client) object.assign -> babel-plugin-object-assign: decrease client size by 2kb

.babelrc

@@ -1,6 +1,9 @@
 {
     "presets": [
       "es2015"
-    ]
+    ],
+    "plugins": [
+      "transform-object-assign"
+  ]
 }
 

client/cloudcmd.js

@@ -8,8 +8,6 @@ window.Emitify = require('emitify');
 
 window.CloudCmd = (config) => {
     window.Promise = window.Promise || require('es6-promise');
-    Object.assign = Object.assign || require('object.assign');
-
     window.Util = require('../common/util');
     window.CloudFunc = require('../common/cloudfunc');
     

package.json

@@ -153,6 +153,7 @@
   "devDependencies": {
     "babel-cli": "^6.18.0",
     "babel-loader": "^6.2.10",
+    "babel-plugin-transform-object-assign": "^6.22.0",
     "babel-preset-es2015": "^6.18.0",
     "coveralls": "^2.11.6",
     "emitify": "^2.1.1",
@@ -168,7 +169,6 @@
     "nodemon": "^1.9.1",
     "nsp": "^2.2.1",
     "nyc": "^10.1.2",
-    "object.assign": "^4.0.4",
     "place": "^1.1.4",
     "readjson": "^1.1.3",
     "recess": "^1.1.9",

webpack.config.js

@@ -72,7 +72,6 @@ function externals(context, request, fn) {
     
     const list = [
         'es6-promise',
-        'object.assign',
     ];
     
     if (list.includes(request))