Merge pull request #1122 from edx/usman/lms1167-pdfjs-update

PdfViewer: Added missing link to compatibility.js

lms/templates/static_pdfbook.html

@@ -13,6 +13,7 @@
 <%static:js group='courseware'/>
 <link rel="stylesheet" href="/static/css/pdfviewer.css"/>
 <script type="text/javascript" src="/static/js/vendor/pdfjs/pdf.js"></script>
+<script type="text/javascript" src="/static/js/vendor/pdfjs/compatibility.js"></script>
 <script type="text/javascript" src="/static/js/pdfviewer.js"></script>
 </%block>