fix: build for ssr package

build/build-ssr.js

@@ -1,12 +1,21 @@
 var rollup = require('rollup')
-var async = require('rollup-plugin-async')
+var babel = require('rollup-plugin-babel')
 var isProd = process.argv[process.argv.length - 1] !== '--dev'
 
 rollup
   .rollup({
     entry: 'packages/docsify-server-renderer/index.js',
     plugins: [
-      async()
+      babel({
+        presets: [
+          [
+            'es2015',
+            {
+              modules: false
+            }
+          ]
+        ]
+      })
     ],
     onwarn: function() {}
   })

package.json

@@ -35,6 +35,7 @@
     "zoom-image": "^0.1.4"
   },
   "devDependencies": {
+    "babel-preset-es2015": "^6.24.1",
     "cssnano": "^3.10.0",
     "eslint": "^3.18.0",
     "eslint-config-vue": "^2.0.2",
@@ -43,7 +44,7 @@
     "postcss": "^5.2.16",
     "postcss-salad": "^1.0.8",
     "rollup": "^0.41.6",
-    "rollup-plugin-async": "^1.2.0",
+    "rollup-plugin-babel": "^2.7.1",
     "rollup-plugin-buble": "^0.15.0",
     "rollup-plugin-commonjs": "^8.0.2",
     "rollup-plugin-node-resolve": "^2.0.0",