Add a div with cython class for embedding

This allow to reuse directly the body and embed it without having to
wrap it in the correct div and have the CSS apply to it.

Cython/Compiler/Annotate.py

@@ -135,7 +135,7 @@ class AnnotationCCodeWriter(CCodeWriter):
         return ''.join(outlist)
 
     def _save_annotation_body(self, lines, code_source_file):
-        outlist = []
+        outlist = [u'<div class="cython">']
         pos_comment_marker = u'/* \N{HORIZONTAL ELLIPSIS} */\n'
         new_calls_map = dict(
             (name, 0) for name in
@@ -170,6 +170,7 @@ class AnnotationCCodeWriter(CCodeWriter):
             outlist.append(u"<pre class='cython line score-%s' onclick='toggleDiv(this)'> %d: %s</pre>\n" % (
                 score, k, line.rstrip()))
             outlist.append(u"<pre class='cython code score-%s'>%s</pre>" % (score, code))
+        outlist.append(u"</div>")
         return outlist