[xml] enhancement of XML Schema content model error reports

[Kasimier Buchcik <kbuchcik 4commerce de>]

Hi,

As of xmlschemas.c rev. 1.97 the new xmlregexp.c functions for
error analysis are integrated into the error reports.

Examples:

1. Unexpected elements:
  "This element is not expected. Expected is one of {http://FOO}'foo',
   {http://BAR}*.";
  If no other elements are expected, "This element is not expected."
  will be reported only.

2. Missing elements:
  "Missing child element(s). Expected is {##other:http//FOO}*"

For every namespace of a wildcard with multiple namespaces, there
will be one reported item.
Example:
  <any namespace="http://FOO urn:foo:bar ##local"/>)
  Will be reported as:
  "Expected is one of {http://FOO}*, {urn:foo:bar}*, *."

Any comments on the output?
I tend to dislike the naked * if using ##local, but
won't change it, if it's OK with you.

Greetings,

Kasimier