Add app up event

src/js/index.js

@@ -372,6 +372,7 @@ var ACTION_APP_UNINSTALL = 'app.uninstall';
 var ACTION_APP_UPDATE = 'app.update';
 var ACTION_APP_LOGIN = 'app.login';
 var ACTION_APP_OOM = 'app.oom';
+var ACTION_APP_UP = 'app.up';
 var ACTION_APP_DOWN = 'app.down';
 var ACTION_APP_TASK_CRASH = 'app.task.crash';
 
@@ -477,7 +478,10 @@ app.filter('eventLogDetails', function() {
             return source.app.manifest.title + ' ran out of memory';
 
         case ACTION_APP_DOWN:
-            return source.app.manifest.title + ' is not reachable';
+            return source.app.manifest.title + ' is down';
+
+        case ACTION_APP_UP:
+            return source.app.manifest.title + ' is back online';
 
         case ACTION_APP_TASK_CRASH:
             return 'Apptask for app with id ' + source.appId + ' crashed';