added xsd:include support, fixed testSchemas behaviour when a schemas

* include/libxml/schemasInternals.h include/libxml/xmlerror.h
  testSchemas.c xmlschemas.c: added xsd:include support, fixed
  testSchemas behaviour when a schemas failed to parse.
* test/schemas/vdv-* result/schemas/vdv-first5_0_0*: added one
  test for xsd:include from Eric Van der Vlist
Daniel
diff --git a/include/libxml/xmlerror.h b/include/libxml/xmlerror.h
index 96439f8..b32b5eb 100644
--- a/include/libxml/xmlerror.h
+++ b/include/libxml/xmlerror.h
@@ -537,6 +537,10 @@
     XML_SCHEMAP_FAILED_PARSE, /* 1765 */
     XML_SCHEMAP_UNKNOWN_PREFIX, /* 1766 */
     XML_SCHEMAP_DEF_AND_PREFIX, /* 1767 */
+    XML_SCHEMAP_UNKNOWN_INCLUDE_CHILD, /* 1768 */
+    XML_SCHEMAP_INCLUDE_SCHEMA_NOT_URI, /* 1769 */
+    XML_SCHEMAP_INCLUDE_SCHEMA_NO_URI, /* 1770 */
+    XML_SCHEMAP_NOT_SCHEMA, /* 1771 */
     XML_SCHEMAV_NOROOT = 1800,
     XML_SCHEMAV_UNDECLAREDELEM, /* 1801 */
     XML_SCHEMAV_NOTTOPLEVEL, /* 1802 */