[datafeed] Allow to override use_cwuri_as_url in configuration of a datafeed source This is necessary because in some case one will want to write parser which create entities not one-to-one related to entities from the distant source (for instance see the `vcrs` cube which create entities holding statistics for code review, while not importing review entities themselves). Ideally we should provide a way to the parser to indicate the source that cwuri should not be used, but that's a start... Closes #3670210

Add some entities
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As manager, you can access to entity creation forms by using the `site management`_ page.

.. _`site management`: manage

As regular user, the index page or the action box may propose some links to create entities according to the context.