Adds a datatypeLibrary-aware datatype resolver to the XML-syntax parser:
the in-scope library is inherited from the nearest ancestor, the default
(empty) library defines only string and token, and the W3C XML Schema
library defines the full built-in set. A type the in-scope library does
not define is an unknown datatype, so the <data>/<value> pattern matches
nothing rather than silently validating.
Adds an nsNameExcept name-class case so nsName with an <except> child
(XML syntax) and prefix:* - name subtraction (compact syntax) narrow a
namespace wildcard. The compact lexer splits prefix:* into a trailing-
colon word plus a star symbol, which the parser now recognizes.
Existing RELAX NG facet tests declared XSD types without the library and
relied on lenient resolution; they now declare the XSD datatypeLibrary,
matching what a conformant processor requires.
