Dont croak if subelement is an honest to god text node in getElementsByTagName

lib/python/StructuredText/STDOM.py

@@ -456,6 +456,7 @@ class Element(Node):
       """
       nodeList = []
       for child in self.getChildren():
+         if not hasattr(child, 'getNodeType'): continue
          if (child.getNodeType()==ELEMENT_NODE and \
              child.getTagName()==tagname or tagname== '*'):