Optimize repository removal

Fixes #662

This PR fix some Issues  with the current workflows and role mappings has some

#### Permission:
 - The  `Delete objects` permission is now only mapped to the `Manager` role
 - The  `_verifyObjectPaste ` method is patched, to allow moving content without `delete Objects` permission
 - The repository workflow add `Delete objects` permission also for the `Administrator` role.
 - The repository workflow drops `List folder contents` permission for the `Administrator` role.
 - The dossier workflow does no longer acquire the `delete Objects` permission, but give it to the `Manager`

#### Repository deletion:
 - Add separate remove action, so that removing is possible without the `folder contents` view. The action is only be displayed when the preconditions are satisfied.
 - Add separate `RepositoryRemover` wich checks that the repository you want to delete does not contains content.
 - Add confirmation view for deleting repositories.


@lukasgraf please have a look ...