Added markdown parsing for comments so links in comments now appear properly.

Also rewrote part of the HTML rewriting code so it doesn't introduce an additional wrapping element in the output which was added due to a html5lib requirements on input.

python/packages/markdown/etree_loader.py

@@ -0,0 +1,31 @@
+
+## Import
+def importETree():
+    """Import the best implementation of ElementTree, return a module object."""
+    etree_in_c = None
+    try: # Is it Python 2.5+ with C implemenation of ElementTree installed?
+        import xml.etree.cElementTree as etree_in_c
+        from xml.etree.ElementTree import Comment
+    except ImportError:
+        try: # Is it Python 2.5+ with Python implementation of ElementTree?
+            import xml.etree.ElementTree as etree
+        except ImportError:
+            try: # An earlier version of Python with cElementTree installed?
+                import cElementTree as etree_in_c
+                from elementtree.ElementTree import Comment
+            except ImportError:
+                try: # An earlier version of Python with Python ElementTree?
+                    import elementtree.ElementTree as etree
+                except ImportError:
+                    raise ImportError("Failed to import ElementTree")
+    if etree_in_c: 
+        if etree_in_c.VERSION < "1.0.5":
+            raise RuntimeError("cElementTree version 1.0.5 or higher is required.")
+        # Third party serializers (including ours) test with non-c Comment
+        etree_in_c.test_comment = Comment
+        return etree_in_c
+    elif etree.VERSION < "1.1":
+        raise RuntimeError("ElementTree version 1.1 or higher is required")
+    else:
+        return etree
+