Add jquery cdn link

Created by: zacechola

Closes #17057 (closed)

_config.yml

@@ -39,3 +39,4 @@ cdn:
   css:            https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css
   css_theme:      https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap-theme.min.css
   js:             https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js
+  jquery:         https://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js