added pebble-js-app.js

src/js/pebble-js-app.js

@@ -0,0 +1,9 @@
+Pebble.addEventListener('ready', function() {
+    console.log('PebbleKit JS ready!');
+});
+
+Pebble.addEventListener('showConfiguration', function() {
+    var url='http://pebble.lastfuture.de/config/supersimple/';
+    console.log('Showing configuration page: '+url);
+    Pebble.openURL(url);
+});