Added anchor.js to docs

.gitignore

@@ -16,4 +16,10 @@ Vagrantfile
 .coverage*
 /.cache
 
+<<<<<<< HEAD
 .pytest_cache/
+=======
+Gemfile
+Gemfile.lock
+_site/
+>>>>>>> 600be0a... Added anchor.js to docs

docs/_includes/ga_tracking.html

@@ -11,3 +11,10 @@
   })();
 
 </script>
+
+<script src="https://cdnjs.cloudflare.com/ajax/libs/anchor-js/4.2.0/anchor.min.js"></script>
+<script>
+document.addEventListener("DOMContentLoaded", function(event) {
+  anchors.add();
+});
+</script>