ServiceWorker (#1243)

- Create service worker to have PWA
 - Add install service worker
 - Add fecth service worker with a persistent cache navigator
 - Add favicon 512x512

front/dist/resources/service-worker.js

@@ -0,0 +1,53 @@
+let CACHE_NAME = 'workavdenture-cache-v1';
+let urlsToCache = [
+    '/'
+];
+
+self.addEventListener('install', function(event) {
+    // Perform install steps
+    event.waitUntil(
+        caches.open(CACHE_NAME)
+            .then(function(cache) {
+                console.log('Opened cache');
+                return cache.addAll(urlsToCache);
+            })
+    );
+});
+
+self.addEventListener('fetch', function(event) {
+    event.respondWith(
+        caches.match(event.request)
+            .then(function(response) {
+                // Cache hit - return response
+                if (response) {
+                    return response;
+                }
+
+                return fetch(event.request).then(
+                    function(response) {
+                        // Check if we received a valid response
+                        if(!response || response.status !== 200 || response.type !== 'basic') {
+                            return response;
+                        }
+
+                        // IMPORTANT: Clone the response. A response is a stream
+                        // and because we want the browser to consume the response
+                        // as well as the cache consuming the response, we need
+                        // to clone it so we have two streams.
+                        var responseToCache = response.clone();
+
+                        caches.open(CACHE_NAME)
+                            .then(function(cache) {
+                                cache.put(event.request, responseToCache);
+                            });
+
+                        return response;
+                    }
+                );
+            })
+    );
+});
+
+self.addEventListener('activate', function(event) {
+    //TODO activate service worker
+});