* xmlschemas.c include/libxml/xmlerror.h include/libxml/xmlschemas.h
  include/libxml/schemasInternals.h: Parsing of <complexContent>
  - handle attribute 'mixed', catch illegal attributes.
  Parsing of <complexType> - handle attributes 'abstract',
  'final' and 'block', catch illegal attributes.
  Validation of complex types - handle abstract types.
  Added handling of default/fixed attributes and element values.
  Per validation option attribute nodes/text nodes are created
  on the instance.
  Added the corresponding constraints for fixed/default.
  Added xmlSchemaSetValidOptions, xmlSchemaGetValidOptions
  to the external API.
  Extended element declaration constraints.
  Got rid of perseverative creation of temporery validation/parser
  contexts.
  Added handling of xsi:schemaLocation and
  xsi:noNamespaceSchemaLocation.
  Fixed xsi:type component resolution if using non-prefixed
  QNames.
* xmlregexp.c xmlschemas.c include/libxml/xmlautomata.h:
  Enabled namespace awareness of the content model if using the
  model group "all".
* test/schemas/bug152470_1.xsd: Removed an "abstract" attribute,
  which broke the test.
* xstc/xstc.py:  Workaround to accomodate case insensitive
  test definitions in ms-test.def.xml (was missing in a previous
  commit).