applied patch from Malcolm Tredinnick fixing errata E20 concerning

* valid.c TODO: applied patch from Malcolm Tredinnick fixing errata
  E20 concerning NMTOKENS and co. validation #153722
* result/VC/AttributeNmtokens test/VC/AttributeNmtokens
  test/VCM/AttributeNmtokens.xml: also added tests from Malcolm
Daniel
diff --git a/parser.c b/parser.c
index 998a97a..4710270 100644
--- a/parser.c
+++ b/parser.c
@@ -2342,7 +2342,7 @@
  *
  * [5] Name ::= (Letter | '_' | ':') (NameChar)*
  *
- * [6] Names ::= Name (S Name)*
+ * [6] Names ::= Name (#x20 Name)*
  *
  * Returns the Name parsed or NULL
  */
@@ -2467,7 +2467,7 @@
  *
  * [5] Name ::= (Letter | '_' | ':') (NameChar)*
  *
- * [6] Names ::= Name (S Name)*
+ * [6] Names ::= Name (#x20 Name)*
  *
  * Returns the Name parsed or NULL. The @str pointer 
  * is updated to the current location in the string.
@@ -2547,7 +2547,7 @@
  *
  * [7] Nmtoken ::= (NameChar)+
  *
- * [8] Nmtokens ::= Nmtoken (S Nmtoken)*
+ * [8] Nmtokens ::= Nmtoken (#x20 Nmtoken)*
  *
  * Returns the Nmtoken parsed or NULL
  */