more types, more coverage more problems fixed Daniel

* gentest.py testapi.c: more types, more coverage
* parser.c parserInternals.c relaxng.c valid.c xmlIO.c
  xmlschemastypes.c: more problems fixed
Daniel
diff --git a/xmlschemastypes.c b/xmlschemastypes.c
index 6dd8cbb..0a1e5b1 100644
--- a/xmlschemastypes.c
+++ b/xmlschemastypes.c
@@ -749,7 +749,7 @@
 xmlSchemaTypePtr
 xmlSchemaGetBuiltInListSimpleTypeItemType(xmlSchemaTypePtr type)
 {
-    if (type->type != XML_SCHEMA_TYPE_BASIC)
+    if ((type == NULL) || (type->type != XML_SCHEMA_TYPE_BASIC))
 	return (NULL);
     switch (type->builtInType) {
 	case XML_SCHEMAS_NMTOKENS: