Doc Anchor Enhancement

This patch makes the documentation's anchors behave like those found in
Markdown when hosted on GitHub.

.docs/css/anchor.css

@@ -0,0 +1,21 @@
+.svg-anchor {
+    float: left;
+    padding-right: 4px;
+    margin-left: -20px;
+    line-height: 1;
+
+    opacity: 0;
+    /*
+    -webkit-transition: opacity 0.2s ease-in-out 0.1s;
+    -moz-transition: opacity 0.2s ease-in-out 0.1s;
+    -ms-transition: opacity 0.2s ease-in-out 0.1s;
+    */
+}
+
+h2:hover .svg-anchor,
+h3:hover .svg-anchor,
+h4:hover .svg-anchor,
+h5:hover .svg-anchor,
+h6:hover .svg-anchor {
+  opacity: 1;
+}

.docs/js/anchor.js

@@ -0,0 +1,11 @@
+$("h2, h3, h4, h5, h6").each(function(i, el) {
+    var $el, svg, id;
+    $el = $(el);
+    id = $el.attr('id');
+    svg = '<svg aria-hidden="true" class="octicon octicon-link" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg>';
+    if (id) {
+        return $el.prepend($("<a />").addClass(
+            "svg-anchor").attr("aria-hidden", "true").attr(
+            "href", "#" + id).html(svg));
+    }
+});

mkdocs.yml

@@ -8,14 +8,15 @@ site_favicon: favicon.png
 extra_css:
   - css/thecodeteam.css
   - css/thecodeteam-font.css
+  - css/anchor.css
   - css/hX.css
   - css/first-of-type.css
   - css/hide-rtd-footer.css
   - css/dropdown.css
+extra_javascript:
+  - js/anchor.js
 markdown_extensions:
   - admonition
-  - toc:
-      permalink: true
 pages:
   - Home: index.md
   - User Guide: