* xmlschemastypes.c xmlschemastypes.h: In preparation to use
  normalized values of facets during validation: changed the
  arguments of some string comparison functions; added a static
  xmlSchemaValidateFacetInternal() with more arguments to be
  more flexible. Prepared XML_SCHEMA_FACET_ENUMERATION validation
  to use the comparison functions. Fixed some assignments in
  xmlSchemaValAtomicType(): total digit count, lo, mi, hi.