Uglify version for production in browsers

Added a post script hook to generate a minify version
for browsers.

Added `unpkg` field in `package.json` for free CDN
at <https://unpkg.com/>.

Added file `package-lock.json` as instructed by npm.

Instructions for use in a browser.

Author: atilacamurca

.gitignore

@@ -1,4 +1,3 @@
 npm-debug.log
 node_modules/
 .DS_Store
-package-lock.json

README.md

@@ -14,12 +14,18 @@ Installation:
 npm install vue-filepond --save
 ```
 
+For browser:
+
+```html
+<script src="https://unpkg.com/vue-filepond"></script>
+```
+
 Usage:
 
 ```vue
 <template>
   <div id="app">
-    
+
     <FilePond
         name="test"
         ref="pond"
@@ -29,7 +35,7 @@ Usage:
         server="/api"
         v-bind:files="myFiles"
         v-on:init="handleFilePondInit"/>
-    
+
   </div>
 </template>
 
@@ -52,7 +58,7 @@ export default {
     methods: {
         handleFilePondInit: function() {
             console.log('FilePond has initialized');
-            
+
             // FilePond instance methods are available on `this.$refs.pond`
         }
     },