Added note about pages being publicly viewable

STUD-1488

cms/templates/edit-tabs.html

@@ -139,6 +139,8 @@
       <div class="bit">
         <h3 class="title-3">${_("What are pages?")}</h3>
         <p>${_("Pages are listed horizontally at the top of your course. Default pages (Courseware, Course info, Discussion, Wiki, and Progress) are followed by textbooks and custom pages that you create.")}</p>
+
+        <p>${_("Note: Pages are publicly visible. If users know the URL of a page, they can view the page even if they are not registered for or logged in to your course.")}</p>
       </div>
       <div class="bit">
         <h3 class="title-3">${_("Custom pages")}</h3>