[urlpublishing] handle sub-types in RestPathEvaluator
Since commit 31a1813d53f3 "[entity/url publishing] fetch_rqlst should
use 'is_instance_of' instead of 'is'", the RestPathEvaluator's input
rset can have more than one etype, so it can't always use sameetypelist.
Related to #3825488
Schema of the data
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First take a look at the data schema_ then try to remember that you are browsing
through a heap of data by applying stylesheets to the results of queries. This
site is not a content management system with items placed in folders. It is an
interface to a database which applies a view to retreived data.
.. _schema: schema