Downloaded and Installed Theme, Now I get A Fatal Error


I am very excited to get going using this service. I just signed up 10 minutes ago, and I uploaded the plugin. When I went to install on my first site RARESOUL.COM, I received this message:

Fatal error: Call to undefined function wp_normalize_path() in /home/content/18/5317818/html/wp-content/themes/upfront/library/servers/class_upfront_admin.php on line 46

Can I get some help on what the fix would be?