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- Configurations can import additional schema components using a new
"%import" directive; this can be used to integrate 3rd-party
components into an application.
- Schemas may be extended using a new "extends" attribute on the
<schema> element.
- Better error messages when elements in a schema definition are
improperly nested.
- The "zconfig" script can now simply verify that a schema definition
is valid, if that's all that's needed.