chore: update building config

Author: JJin

.babelrc

@@ -6,6 +6,6 @@
     "react"
   ],
   "plugins": [
-    "transform-runtime"
+    "external-helpers"
   ]
 }

package.json

@@ -25,7 +25,7 @@
   "devDependencies": {
     "babel-core": "^6.26.0",
     "babel-eslint": "^8.2.2",
-    "babel-plugin-transform-runtime": "^6.23.0",
+    "babel-plugin-external-helpers": "^6.22.0",
     "babel-preset-env": "^1.6.1",
     "babel-preset-react": "^6.24.1",
     "eslint": "^4.18.1",

rollup.config.js

@@ -11,6 +11,9 @@ export default {
     file: pkg.module
   }],
   plugins: [
-    babel(),
+    babel({ runtimeHelpers: true }),
+  ],
+  external: [
+    'react'
   ]
 };