Fix greedy intrusion of split_test documentation

cms/templates/container.html

@@ -103,7 +103,7 @@ from django.utils.translation import ugettext as _
                 </div>
             </article>
             <aside class="content-supplementary" role="complementary">
-                % if not is_unit_page:
+                % if xblock.category == 'split_test':
                     <div class="bit">
                         <h3 class="title-3">${_("Adding components")}</h3>
                         <p>${_("Select a component type under {em_start}Add New Component{em_end}. Then select a template.").format(em_start='<strong>', em_end="</strong>")}</p>
@@ -119,8 +119,7 @@ from django.utils.translation import ugettext as _
                     <div class="bit external-help">
                         <a href="${get_online_help_info(online_help_token())['doc_url']}" target="_blank" class="button external-help-button">${_("Learn more about component containers")}</a>
                     </div>
-                % endif
-                % if is_unit_page:
+                % elif is_unit_page:
                     <div id="publish-unit"></div>
                     <div id="publish-history" class="unit-publish-history"></div>
                     <div class="unit-location is-hidden">