[migration] unify process_script command
- simplify wrapper by putting the logic in the migration module
- enable sql script in shell invocation
- adjust cmd_process_script docstring in interactive shell
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.