Add array to control which section gets collapsed (pytorch#1372)

Co-authored-by: Brandon Green <[email protected]>

Author: Bgreen23

_templates/layout.html

@@ -73,5 +73,10 @@
   src="https://www.facebook.com/tr?id=243028289693773&ev=PageView
   &noscript=1"/>
 </noscript>
+
+<script type="text/javascript">
+  var collapsedSections = [];
+</script>
+
 <img height="1" width="1" style="border-style:none;" alt="" src="https://www.googleadservices.com/pagead/conversion/795629140/?label=txkmCPmdtosBENSssfsC&amp;guid=ON&amp;script=0"/>
 {% endblock %}