Verify examples integrity/correctness against internal model

[gunnar-mb]

Examples are written both in the static text of the specification, and in the written in the text strings that make up documentation for each of the item types in the internal model (this text also gets copied into the spec during the generation of docs from the model).

It would be really nice(tm) if examples were somehow extracted and formally verified to be correct according to the model. The design of this is however very TBD. Open for suggestions.