Update to page help on new Pages page in Studio

STUD-1458

Modified the edit-tabs template and the preview-lms-staticpages image
used in the modal.

cms/templates/edit-tabs.html

@@ -99,12 +99,16 @@
 
     <aside class="content-supplementary" role="complimentary">
       <div class="bit">
-        <h3 class="title-3">${_("What are Pages?")}</h3>
-        <p>${_("Pages are the items that appear in your course navigation. Some are required and cannot be moved or edited (Courseware, Course info, Discussion, Progress, Wiki), and you can add your own custom pages to hold additional content you want to provide to your students, like a syllabus, calendar, or handouts.")}</p>
+        <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>
       </div>
       <div class="bit">
-        <h3 class="title-3">${_("How do Pages look to students in my course?")}</h3>
-        <p>${_("Pages are the navigational items that appear across the top of your course.")} <br /> <a rel="modal" href="#preview-lms-staticpages">${_("See an example")}</a></p>
+        <h3 class="title-3">${_("Custom pages")}</h3>
+        <p>${_("You can create and edit custom pages to provide students with additional course content. For example, you can create pages for the grading policy, course slides, and a course calendar. ")} </p>
+      </div>
+      <div class="bit">
+        <h3 class="title-3">${_("How do pages look to students in my course?")}</h3>
+        <p>${_("Students see the default and custom pages at the top of your course and use these links to navigate.")} <br /> <a rel="modal" href="#preview-lms-staticpages">${_("See an example")}</a></p>
       </div>
     </aside>
 
@@ -115,7 +119,7 @@
   <h3 class="title">${_("Pages in Your Course")}</h3>
   <figure>
     <img src="${static.url("img/preview-lms-staticpages.png")}" alt="${_('Preview of Pages in your course')}" />
-    <figcaption class="description">${_("The names of your Pages appear in your course's main navigation bar, along with Courseware, Course Info, Discussion, Wiki, and Progress.")}</figcaption>
+    <figcaption class="description">${_("Pages appear in your course's top navigation bar. The default pages (Courseware, Course Info, Discussion, Wiki, and Progress) are followed by textbooks and custom pages.")}</figcaption>
   </figure>
 
   <a href="#" rel="view" class="action action-modal-close">