Fix "Modified wf condition to get transitions to be available even if causality state is in "draft""

- Now when a delivery is cloned and since Julien commit 5c09e2, scripts are no longer called to "start_building" and  "update_causality_state", the delivery therefore remains in draft state. Transitions that were waiting for the the delivery to be in a "solved" state were not available any longer.

this was actually "dry run"

Also minor fixes on comments and make a set of base categories for faster
lookups

* no limit instead of 1 by default.
* no listbox rendering until the dialog is updated so that we get the dialog quickly.

Supply Lines from trade conditions should not be applicable once the trade condition is invalidated / deleted

pyPdf goes in an infinite loop when PdfFileReader are created on an empty file.

BudgetCell_view is installed by erp5_budget and this bt5 is not dependency of erp5_project. Then, if erp5_project is installed Project Cell is broken.

DeliveryCell_view is more appropriated because it is installed by erp5_trade that is a erp5_project dependency

This test was using non existant categories.

Activity is expected to be appended to message_list_dict's value already,
no need to append it to queued_activity.
In turn, this allows getting rid of _prepare_args.

_registered is already declared on TM superclass.
_p_* are only useful on subclasses of persistence.Persistent. TM is not.

This should never match, because published API does not provide access to
Message when registering it (this is intentional).
Also, this search is O(n), which makes activity creation complexity
O(n**2).