try to make the copy function work for node of type

* tree.c: try to make the copy function work for node of
  type XML_DOCUMENT_FRAG_NODE, they are only created by the
  DOM layers though, not libxml2 itself.
Daniel
diff --git a/tree.c b/tree.c
index 4c05747..faf33f7 100644
--- a/tree.c
+++ b/tree.c
@@ -3046,6 +3046,7 @@
         case XML_TEXT_NODE:
         case XML_CDATA_SECTION_NODE:
         case XML_ELEMENT_NODE:
+        case XML_DOCUMENT_FRAG_NODE:
         case XML_ENTITY_REF_NODE:
         case XML_ENTITY_NODE:
         case XML_PI_NODE:
@@ -3065,7 +3066,6 @@
 #endif
 	    return((xmlNodePtr) xmlCopyDoc((xmlDocPtr) node, recursive));
         case XML_DOCUMENT_TYPE_NODE:
-        case XML_DOCUMENT_FRAG_NODE:
         case XML_NOTATION_NODE:
         case XML_DTD_NODE:
         case XML_ELEMENT_DECL: