adjusted accordion feature by removing setting for this

You now have to manually adjust a few things in the sidebar.html if you
do not want the accordion feature.

doc_configuration_settings.md

@@ -39,7 +39,6 @@ Note that you can define arbitrary key-value pairs in the configuration file, an
 | **site_title**| Appears in the webpage title area (on the browser tab, not in the page viewing area). In the sample theme files, the site title is the "page name | homepage title." |       
 | **port**  | Required  | The port used in the preview mode. This is only for the live preview and doesn't affect the published output. If you serve multiple outputs simultaneously, the port must be unique.  |        
 | **feedback_email**    | Gets configured as the email address in the Send Feedback button in the top navigation bar.|
-| **sidebar_accordion**  | Optional  | Boolean. The default value is true. Whether you want the navigation sidebar to use the accordion effect or not. The accordion effect means when you expand a section, the other sections automatically collapse. If you put `false`, then you can expand multiple sections at once. At the bottom of the navigation sidebar, two links will appear: Collapse All and Expand All. |  
 | **disqus_shortname** | Optional   | The disqus site shortname, which is used for comments. If you don't want comment forms via disqus, leave this blank or omit it altogether and Disqus won't appear.   |         
 | **markdown**  | Required  | The processor to use for Markdown. This is a Jekyll-specific setting. Use `redcarpet`. Another option is `kramdown`. However, my examples will follow redcarpet.   |     
 | **redcarpet**  | Required  | Extensions used with redcarpet. You can read more about them by searching for redcarpet extensions online.    |