Update README.rdoc

Author: Fivell

README.rdoc

@@ -6,7 +6,7 @@ easy change sidebar position with activeadmin (tested with active_admin-0.5.0)
 
 Add including of css file 
 
-  @import "active_admin_sidebar"; 
+  @import "active_admin_sidebar/index"; 
 
 to the  app/assets/stylesheets/active_admin.css.scss