use marked for markdown

IPython/frontend/html/notebook/static/js/notebookmain.js

@@ -42,7 +42,6 b' $(document).ready(function () {'
     var baseProjectUrl = $('body').data('baseProjectUrl')
 
     IPython.page = new IPython.Page();
-    IPython.markdown_converter = new Markdown.Converter();
     IPython.layout_manager = new IPython.LayoutManager();
     IPython.pager = new IPython.Pager('div#pager', 'div#pager_splitter');
     IPython.quick_help = new IPython.QuickHelp('span#quick_help_area');

IPython/frontend/html/notebook/static/js/textcell.js

@@ -315,9 +315,9 b' var IPython = (function (IPython) {'
         if (this.rendered === false) {
             var text = this.get_text();
             if (text === "") { text = this.placeholder; }
-            text = IPython.mathjaxutils.remove_math(text)
-            var html = IPython.markdown_converter.makeHtml(text);
-            html = IPython.mathjaxutils.replace_math(html)
+            text = IPython.mathjaxutils.remove_math(text);
+            var html = marked.parser(marked.lexer(text));
+            html = IPython.mathjaxutils.replace_math(html);
             try {
                 this.set_rendered(html);
             } catch (e) {

IPython/frontend/html/notebook/templates/notebook.html

@@ -206,7 +206,7 b' class="notebook_app"'
 <script src="{{ static_url("components/codemirror/mode/rst/rst.js") }}" charset="utf-8"></script>
 <script src="{{ static_url("components/codemirror/mode/markdown/markdown.js") }}" charset="utf-8"></script>
 
-<script src="{{ static_url("pagedown/Markdown.Converter.js") }}" charset="utf-8"></script>
+<script src="{{ static_url("components/marked/lib/marked.js") }}" charset="utf-8"></script>
 
 <script src="{{ static_url("prettify/prettify.js") }}" charset="utf-8"></script>
 <script src="{{ static_url("dateformat/date.format.js") }}" charset="utf-8"></script>