[entity] add an official ``cw_etype`` property for entity
This property holds the CWEtype id of the entity. This information was previously
available through __regid__ but this is an ugly public API. So we have a new
clean public API. The ``dc_type()`` method could not be used as it is
translated.
(closes #2793792)
Latest changes
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* table of `all latest changes`_
Links below is providing useful RQL query example.
.. _all latest changes: view?rql=Any+M%2CX+WHERE+X+modification_date+M+ORDERBY+M+DESC+LIMIT+30