Avoid running out of file descriptors when backing up many objects in the trash upon bt5 installation.

Before, when installing a bt5 whose format has changed, many subobjects may
end up being backup up, but it keeps one FD per subobject, thus easily
reaching the limit of 1024 FDs (as given by ulimit -Sn/-Hn).

This is a followup of b71e5a73 specific to TrashTool as that commit seems to
only fix the issue when TrashTool is not used.

Upon Business Path Item installation, update Local Roles of objects whose Portal Types defines Roles.

Before, Local Roles were not updated upon Path Item installation, thus leading
to security issues (such as Trade Model Line). This avoids ugly hacks in
Upgrader and in tests as well.

To show a workflow dialog which absolutely fail is not good.

Improve error handling on Workflow_statusModify. If divergence is solved by other user, then show a nice message.

Uid must be always consistent. If uid is changed, then workflow action which user selected is applied to different workflow and it causes different result.

Improve error handling on Workflow_statusModify. If requested transition is not available, then show a nice message.

PasswordTool_viewResetPassword/text_content from erp5_core wrongly requires
Field Library in erp5_web and EmbeddedFile_view/my_description from erp5_base
wrongly requires Field Library in erp5_dms.

If an user has set SVN working copies in its preferences, it cannot be
modified anymore after upgrade.

Now both ascending arrow and descending arrow are displayed in title column
and user can sort in specific order explicitly. User also can sort multiple
columns by click without using sort-on-dialog.

Fix error message of StringAttributeMatch Constraint incorrectly renamed after migration to ZODB (78e2ae32).

92aa42c378783603e90f7ff27208034bdfe5a5e5 reintroduced the random failure. This
restores the same workaround using the 3 item sort syntax

It should prevent a random failure

This way mysql will probably merge this with other constraints on
stock.portal_type when portal_type= is passed.

We were joining catalog for section, node and resource, mainly in order to
expose _title and _relative_url in brains. We just need to select the
corresponding uids and let brains do another catalog search to get the object
when accessed.
Note that erp5_banking_core is not updated

Change the person_view / career_view if ERP5 HR is installed so that a person's career only defines the relation to a position.
Display in position history the list of related person's careers.
Be able to assign a person to a position (in an assignment) like it is possible for a project.