This reverts commit fa128ff7.

This is only cosmetics.

Hard links are only used for the initial clone.
On next runs, the working copies diverge and this wastes space on disk.

erp5_officejs_afs_directory: clean up page layout, provide fallback images integrate wikipedia content

To make sure request is different and reports do not affect
one another

so that we check that at_date in OrderModule_activateGetOrderStatList
works as inclusive

Also:
- fix parameter name to be the same as what request has
- Formatting and trailing whitespaces fixes

Otherwise, reset is not triggered when changing a 'Standard Property'
ZODB Property Sheet (through dynamic_class_generation_interaction_workflow
ChangeProperty_resetDynamicClasses Interaction). Also, add Unit Tests to
check that this Interaction is properly called.

'Base Category' was also removed in 687fedda but this does not seem to be
an issue as 'Category Property' and 'Dynamic Category Property' only use
the ID, and thus this is handled by PropertySheet_resetDynamicClasses
Interaction (_delObject/_setObject will be called).

Allows being compatible with future, improved PAS plugin features.
Also, drop a few useless imports.

In ERP5User, getId() is the identifier, but for SpeicalUser, like
Anonymous User, System Processes etc., getId() is None.