add serviceworker demo

Examples/ServiceWorker/index.js

@@ -1,21 +1,31 @@
 /* global Y, Quill */
 
+// register yjs service worker
+if('serviceWorker' in navigator){
+  // Register service worker
+  // it is important to copy yjs-sw-template to the root directory!
+  navigator.serviceWorker.register('./yjs-sw-template.js').then(function(reg){
+    console.log("Yjs service worker registration succeeded. Scope is " + reg.scope);
+  }).catch(function(err){
+    console.error("Yjs service worker registration failed with error " + err);
+  })
+}
+
 // initialize a shared object. This function call returns a promise!
 Y({
   db: {
     name: 'memory'
   },
   connector: {
-    name: 'webworker',
-    url: '../bower_components/y-webworker/yjs-webworker.js',
-    room: 'WebWorkerExample2'
+    name: 'serviceworker',
+    room: 'ServiceWorkerExample2'
   },
   sourceDir: '/bower_components',
   share: {
     richtext: 'Richtext' // y.share.richtext is of type Y.Richtext
   }
 }).then(function (y) {
-  window.yQuill = y
+  window.yServiceWorker = y
 
   // create quill element
   window.quill = new Quill('#quill', {

Examples/ServiceWorker/yjs-sw-template.js

@@ -0,0 +1,22 @@
+/* eslint-env worker */
+
+// copy and modify this file
+
+self.DBConfig = {
+  name: 'indexeddb'
+}
+self.ConnectorConfig = {
+  name: 'websockets-client',
+  // url: '..',
+  options: {
+    jsonp: false
+  }
+}
+
+importScripts(
+  '/bower_components/yjs/y.js',
+  '/bower_components/y-memory/y-memory.js',
+  '/bower_components/y-indexeddb/y-indexeddb.js',
+  '/bower_components/y-websockets-client/y-websockets-client.js',
+  '/bower_components/y-serviceworker/yjs-sw-include.js'
+)

y.es6

@@ -1,6 +1,6 @@
 /**
  * yjs - A framework for real-time p2p shared editing on any data
- * @version v12.1.6
+ * @version v12.1.7
  * @link http://y-js.org
  * @license MIT
  */