lot of bug fixes, cleanup, starting to add proper namespace support too.

* xmlschemas.c xmlschemastypes.c include/libxml/xmlerror.h
  include/libxml/schemasInternals.h: lot of bug fixes, cleanup,
  starting to add proper namespace support too.
* test/schemas/* result/schemas/*: added a number of tests
  fixed the result from some regression tests too.
Daniel
diff --git a/test/schemas/all.xsd b/test/schemas/all.xsd
new file mode 100644
index 0000000..b2e70e3
--- /dev/null
+++ b/test/schemas/all.xsd
@@ -0,0 +1,16 @@
+<?xml version="1.0"?>
+<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
+  <xsd:complexType name="PurchaseOrderType">
+    <xsd:sequence>
+      <xsd:all>
+        <xsd:element name="shipTo" type="USAddress"/>
+        <xsd:element name="billTo" type="USAddress"/>
+        <xsd:element name="items" type="Items"/>
+      </xsd:all>
+      <xsd:sequence>
+        <xsd:element ref="comment" minOccurs="0" maxOccurs="unbounded"/>
+      </xsd:sequence>
+    </xsd:sequence>
+    <xsd:attribute name="orderDate" type="xsd:date"/>
+  </xsd:complexType>
+</xsd:schema>