Create an issue for CE xsi type

[duglin]

See: #1179

assigned to @clemensv

was an old agenda AI

[github-actions]

This issue is stale because it has been open for 30 days with no
activity. Mark as fresh by updating e.g., adding the comment /remove-lifecycle stale.

[duglin]

ping @clemensv

[github-actions]

This issue is stale because it has been open for 30 days with no
activity. Mark as fresh by updating e.g., adding the comment /remove-lifecycle stale.

[duglin]

Jon will look at the .Net impl w.r.t. xml and see where were left off the XML work to see what needs to be done to make it all real

[duglin]

Closing due to inactivity - added to XML spec, see #1376