Add administrator preferences

src/invidious/views/template.ecr

@@ -89,12 +89,14 @@
             <i class="icon ion-ios-cog"></i>
           </a>
         </div>
+        <% if config.login_enabled %>
         <div class="pure-u-1-3">
           <a href="/login?referer=<%= env.get?("current_page") %>" class="pure-menu-heading">
             <%= translate(locale, "Login") %>
           </a>
         </div>
         <% end %>
+        <% end %>
         </div>
       </div>
       <%= content %>