Update bootstrap.py
Remove clear-and-rebuild folder action.

We have already removed the view but we seem to have forgotten to remove the
configured action.
Update bootstrap.py.
Merge pull request #651 from 4teamwork/deif-remove-clearandrebuild

Remove clear-and-rebuild folder action.
Task byline: Use adminUnit abbreviation instead of label for sequence_number display.

For example: `AFI 234` instaed of `Amt fuer Informatik 234`
Merge pull request #646 from 4teamwork/pg_task_byline_sequencenumber

Task byline: Use adminUnit abbreviation instead of label for sequence_number display.
Dropped no longer used AccessInboxAllowed view.
Added new type InboxContainer.

Used in setup's with multiple org_units per admin_unit, to store all inboxes (each for every org_unit).
Dropped Main- and Subinbox implementation, includings redirects on Maininbox etc.

This functionality is now covered by the InboxContainer type.
Added upgradestep which converts Main-Inboxes to InboxContainers.
HistoryViewlet Tests: Fixed isolation.

Reset `DownloadConfirmationHelper` state in `tearDown`, to avoid having inpacts of other tests.
Merge pull request #652 from 4teamwork/pg_inbox_container

Add new type Inbox Container
Fixed mail download for mails with already CRLF.
Merge pull request #653 from 4teamwork/pg_mail_download_fix

Fixed mail download for mails with already CRLF.
Forwarding Transitioncontroller: Fixed assign_to_dossier check.

Right now the `assign_to_dossier` (etc.) guard does not work correctly, when a forwarding has a responsible user without agency_group belonging. This results that the responsible user of the forwarding can't do any action.

This commit solves this problem.
Merge pull request #655 from 4teamwork/pg_inbox_guard_fix

Forwarding Transitioncontroller: Fixed assign_to_dossier check.
Dossier responsible field: use current admin unit's users, instead of only
current orgunit's users.

In a setup with multiple org_units per admin_unit, an limitiation that
only user assigned to the current org_units for the dossier responsibilty
has no additional benefit but rather lead to problems, when a user is
assigned to multiple org_units.
Merge pull request #656 from 4teamwork/pg_dossier_responsible_vocabulary

Dossier responsible field: use current admin unit's users, instead of only current orgunit's users.