fix(client): Use supported shim path.

dignifiedquire · dignifiedquire · commit 184f12e415fa · 2015-08-05T09:28:21.000+02:00
Thanks to @zloirock for pointing this out.
diff --git a/client/main.js b/client/main.js
@@ -1,7 +1,7 @@
 /* global io */
 /* eslint-disable no-new */
 
-require('core-js/modules/es5')
+require('core-js/es5')
 var Karma = require('./karma')
 var StatusUpdater = require('./updater')
 var util = require('./util')
