Add ability to show specific concert via a URL parameter

The |concert| parameter can now be used to show a specific concert.

Change-Id: I85ce519296c8a3d5061021f57391290cd4e16520
diff --git a/sw.js b/sw.js
index 90ce2de..5ac8d72 100644
--- a/sw.js
+++ b/sw.js
@@ -1,4 +1,4 @@
-var CACHE_NAME = 'all-v1.1.2';
+var CACHE_NAME = 'all-v1.1.3';
 var urlsToCache = [
   '/',
   '/css/styles.css',