Stanfordize logged-in view of find courses page

This is nearly a dup of the styling we do for the main index.html
template, but it's a different view since the user is logged in to
the site.

lms/templates/courseware/courses.html

@@ -5,13 +5,13 @@
 <%block name="title"><title>Courses</title></%block>
 
 <section class="find-courses">
-  <header class="search" style="background: url('/static/images/homepage-bg.jpg')">
+  <header class="search">
     <div class="inner-wrapper main-search">
       <hgroup>
         <div class="logo">
-          <img src="${static.url('images/edx_bw.png')}" />
+          <img src="${static.url('themes/stanford/images/seal.png')}" />
         </div>
-        <h2>Explore free courses from leading universities.</h2>
+        <h2>Explore free courses from Stanford University</h2>
       </hgroup>
     </div>
   </header>