CVE-2012-0037

Enforce entity loading policy in raptor_libxml_resolveEntity
and raptor_libxml_getEntity by checking for file URIs and network URIs.

Add RAPTOR_OPTION_LOAD_EXTERNAL_ENTITIES / loadExternalEntities for
turning on loading of XML external entity loading, disabled by default.

This affects all the parsers that use SAX2: rdfxml, rss-tag-soup (and
aliases) and rdfa.
raptor_rdfxml_element_content_type_as_string(raptor_rdfxml_element_content_type type) 
{
  if(type > RAPTOR_RDFXML_ELEMENT_CONTENT_TYPE_LAST)
    return "INVALID";
  return rdf_content_type_info[type].name;
}

raptor_rdfxml_element_content_type_as_string(raptor_rdfxml_element_content_type type) 
{
  if(type > RAPTOR_RDFXML_ELEMENT_CONTENT_TYPE_LAST)
    return "INVALID";
  return rdf_content_type_info[type].name;
}
