Simplify the new template rendering

- No extra template code is required for any new page
- All loaded in base.html or page_base.html
- Oh, so clean!

InvenTree/templates/base.html

@@ -83,6 +83,7 @@
                         {% block sidebar %}
                         <!-- Sidebar goes here -->
                         {% endblock %}
+                        {% include "plugin/panel_menu.html" %}
                         {% include "sidebar_toggle.html" with target='sidebar' %}
                     </ul>
                 </div>
@@ -210,7 +211,7 @@
 
 $(document).ready(function () {
 
-    {% include "panel/plugin_javascript.html" %}
+    {% include "plugin/panel_js.html" %}
 
 {% block js_ready %}
 {% endblock %}