Complete refactor of sidenav

- Reduced DOM complexity
- Less styles overall
- Added an icon in the navbar to show version number
- Still needs an eslint ignore

ui/src/side_nav/components/NavItems.js

@@ -35,10 +35,6 @@ const NavHeader = React.createClass({
   render() {
     const {link, title, useAnchor} = this.props
 
-    if (!link) {
-      return <div className="sidebar-menu--heading">{title}</div>
-    }
-
     // Some nav items, such as Logout, need to hit an external link rather
     // than simply route to an internal page. Anchor tags serve that purpose.
     return useAnchor

ui/src/side_nav/containers/SideNav.js

@@ -83,9 +83,16 @@ const SideNav = React.createClass({
             />
           </NavBlock>
           <div className="sidebar--bottom">
-            <NavBlock icon="heart">
-              <NavHeader title="Woogles" />
-            </NavBlock>
+            <div className="sidebar--item">
+              <div className="sidebar--square">
+                <span className="sidebar--icon icon zap" />
+              </div>
+              <div className="sidebar-menu">
+                <div className="sidebar-menu--heading">
+                  Version: {VERSION}{/* eslint no-undef */}
+                </div>
+              </div>
+            </div>
             {showLogout
               ? <NavBlock icon="user" className="sidebar--item-last">
                   <NavHeader

ui/src/style/layout/sidebar.scss

@@ -151,6 +151,7 @@ $sidebar-menu--gutter: 18px;
   @include gradient-h($sidebar-menu--item-bg-hover,$sidebar-menu--item-bg-hover-accent);
   color: $sidebar-menu--item-text-hover;
 }
+.sidebar-menu--heading,
 .sidebar-menu--heading:link,
 .sidebar-menu--heading:visited,
 .sidebar-menu--heading:active,