When images are deleted, the ImageViewUtilities give
the ImageInfos to the DIO. In the ImageViewUtilities,
the ids of the deleted images are buffered in a list and given to the
AlbumManager via Signal-Slot-communication. I do that since in database
layer, only the URIs of the images are present and getting the image ids is
unnecessary effort. Since the AlbumManager already has all SAlbums, it is
easy to first get all SAlbums that represent DuplicateSearches (I implemented
a method to get all SAlbums by type) and then get all those albums that
contain the deleted images (SearchXmlReader is needed here).

In order to have a good performance and do no unnecessary work, the AlbumManager unites
all image ids from the SAlbums to update and subtracts the ids of the deleted images (set operations).
This way, I am able to communicate the set of images to rescan to the FindDuplicatesView.
Before notifying the FindDuplicatesView, I delete all SAlbums that should be updated.
The reason: Consider an SAlbum that contained two duplicates - the original image and the now deleted
image. If I start a normal duplicates search, no SAlbum will be created for the original image and
the SAlbum will thus not be updated and should not be in the final result set.

Since I now know the ids of the images to rescan, I notify the FindDuplicatesView.
But now I do not have albums to search in - and in fact this would not really be performant since
uninvolved images would be scanned. Thus, I extended the DuplicatesFinder with a new constructor
for searching for duplicates in a set of images. This could be applicable in other situations, too.
To make this work, I extended the DB-Jobinfo with a switch for update of duplicates where the
set of images is and not the albums and tags is used for duplicates search. This way, I can set the
image ids and the update flag in the job info. The DBJob triggers a new variant of rebuildDuplicates
in haariface where the image ids are taken directly.

With this approach, only the SAlbums that need to be updated are updated. SAlbums are only lost,
if no duplicates exist due to deletion which is appropriate. Previously not existing SAlbums cannot be created
since no new images are involved.

BUGS: 261417
FIXED-IN: 5.4.0