Other in Graphics
Factorize sync albums metadata and batch sync metadata tool to just one named MetadataSynchronizer
Port this one to ProgressManager.
Note : this batch tool can be used to sync metadata to DB and vis-versa, for an image list, one album, or whole collection of albums.
Marcel : read Metadata from Images to sync DB is multithreaded, through CollectionScanner.
Write Metadata from DB to images is not yet multithreaded. Still TODO...
At least, only on implementation need to be mutithreaded in the future.