feat: Add docsify version to $window.docsify object (#641)

Fix #521

Please makes sure these boxes are checked before submitting your PR, thank you!

* [ x ] Make sure you are merging your commits to `master` branch.
* [ x ] Add some descriptions and refer relative issues for you PR.
* [ x ] DO NOT include files inside `lib` directory.

build/build.js

@@ -8,12 +8,14 @@ const isProd = process.env.NODE_ENV === 'production'
 const version = process.env.VERSION || require('../package.json').version
 const chokidar = require('chokidar')
 const path = require('path')
+const json = require('rollup-plugin-json')
 
 const build = function(opts) {
   rollup
     .rollup({
       input: opts.input,
       plugins: (opts.plugins || []).concat([
+        json(),
         buble(),
         commonjs(),
         nodeResolve(),

package.json

@@ -65,6 +65,7 @@
     "rollup-plugin-async": "^1.2.0",
     "rollup-plugin-buble": "^0.18.0",
     "rollup-plugin-commonjs": "^8.2.6",
+    "rollup-plugin-json": "^3.1.0",
     "rollup-plugin-node-resolve": "^3.0.0",
     "rollup-plugin-replace": "^2.0.0",
     "rollup-plugin-uglify": "^2.0.1",

src/core/config.js

@@ -1,4 +1,5 @@
 import {merge, hyphenate, isPrimitive, hasOwn} from './util/core'
+import {version as pkgVersion} from './../../package.json'
 
 export default function () {
   const config = merge(
@@ -64,6 +65,7 @@ export default function () {
     }
   }
 
+  config.version = pkgVersion
   window.$docsify = config
 
   return config