xmlschema-formal: wildcard processing

1) Section 3.2 fails to define the difference between wildcards with strict,
lax, and skip processing.

2) Use of a namespace prefix is only meaningful within the scope of the
appropriate namespace declaration.  Use of the "baz:" prefix in a wildcard,
therefore, is not clear.  The same problem applies to section 2.2.2 where
the "xsi:" prefix is used within schema component constructors without being
declared.

-Ray