Stanfordize static 404 and 500 pages

Adjust language and set email to the appropriate email (bugs@ or
techsupport@class.stanford.edu)

lms/templates/static_templates/404.html

@@ -4,5 +4,5 @@
 
 <section class="outside-app">
   <h1>Page not found</h1>
-  <p>The page that you were looking for was not found. Go back to the <a href="/">homepage</a> or let us know about any pages that may have been moved at <a href="mailto:technical@edx.org">technical@edx.org</a>.</p>
+  <p>The page that you were looking for was not found. Go back to the <a href="/">homepage</a> or let us know about any pages that may have been moved at <a href="mailto:techsupport@class.stanford.edu">techsupport@class.stanford.edu</a>.</p>
 </section>

lms/templates/static_templates/server-error.html

 <%inherit file="../main.html" />
 
 <section class="outside-app">
-  <h1>There has been a 500 error on the <em>edX</em> servers</h1>
-  <p>Please wait a few seconds and then reload the page. If the problem persists, please email us at <a href="mailto:technical@edx.org">technical@edx.org</a>.</p>
+  <h1>There has been a 500 error on the <em>Stanford Online</em> servers</h1>
+  <p>Our staff is currently working to get the site back up as soon as possible. Please email us at <a href="mailto:bugs@class.stanford.edu">bugs@class.stanford.edu</a> to report any problems or downtime.</p>
 </section>