feat(plugin): auto-install for CDN usage (script tag)

fix #213

README.md

@@ -67,6 +67,8 @@ Write your suggestions, glad to add.
 
 ## Get started
 
+### NPM
+
 1. Import this plugin, css (theme) and add plugin via `Vue.use`:
 ```js
 import { CoolSelectPlugin } from 'vue-cool-select'
@@ -106,6 +108,23 @@ export default {
 />
 ```
 
+### Browser (CDN)
+
+Include v-tooltip in the page.
+
+```html
+<script src="https://unpkg.com/vue-cool-select"></script>
+
+<!-- paste the line below only if you need "bootstrap" theme -->
+<link rel="stylesheet" href="https://unpkg.com/vue-cool-select@3.0.2/dist/themes/bootstrap.css">
+<!-- paste the line below only if you need "material-design" theme -->
+<link rel="stylesheet" href="https://unpkg.com/vue-cool-select@3.0.2/dist/themes/material-design.css">
+```
+
+If Vue is detected in the Page, the plugin is installed automatically.
+
+---
+
 Documentation and examples [here](https://iliyazelenko.github.io/vue-cool-select).
 
 #### TODO

src/main.js

@@ -1,10 +1,11 @@
 import mergeDeep from '~/helpers'
+import CoolSelect from '~/component.vue'
 
 export const CoolSelectPlugin = new Singleton()
 export { default as EventEmitter } from '~/eventEmitter'
 export { default as component } from '~/component.vue'
-export { default as CoolSelect } from '~/component.vue'
 export { default as VueCoolSelect } from '~/component.vue'
+export { CoolSelect }
 
 function Singleton () {
   return {
@@ -22,3 +23,17 @@ function Singleton () {
     }
   }
 }
+
+let GlobalVue = null
+
+if (typeof window !== 'undefined') {
+  GlobalVue = window.Vue
+} else if (typeof global !== 'undefined') {
+  GlobalVue = global.Vue
+}
+if (GlobalVue) {
+  // Automatic installation if Vue has been added to the global scope.
+  GlobalVue.use(CoolSelectPlugin)
+  GlobalVue.component('cool-select', CoolSelect)
+  GlobalVue.component('vue-cool-select', CoolSelect)
+}