Massive JavaScript cleanup

- Use JSX for templates
- Docblock/comment everything
- Mostly passes ESLint (still some work to do)
- Lots of renaming, refactoring, etc.

CSS hasn't been updated yet.

js/forum/src/utils/drawer.js

@@ -1,12 +1,53 @@
+/**
+ * The `Drawer` class controls the page's drawer. The drawer is the area the
+ * slides out from the left on mobile devices; it contains the header and the
+ * footer.
+ */
 export default class Drawer {
+  constructor() {
+    // Set up an event handler so that whenever the content area is tapped,
+    // the drawer will close.
+    $('.global-content').click(e => {
+      if (this.isOpen()) {
+        e.preventDefault();
+        this.hide();
+      }
+    });
+  }
+
+  /**
+   * Check whether or not the drawer is currently open.
+   *
+   * @return {Boolean}
+   * @public
+   */
+  isOpen() {
+    return $('body').hasClass('drawer-open');
+  }
+
+  /**
+   * Hide the drawer.
+   *
+   * @public
+   */
   hide() {
     $('body').removeClass('drawer-open');
   }
 
+  /**
+   * Show the drawer.
+   *
+   * @public
+   */
   show() {
     $('body').addClass('drawer-open');
   }
 
+  /**
+   * Toggle the drawer.
+   *
+   * @public
+   */
   toggle() {
     $('body').toggleClass('drawer-open');
   }