- ViewportController now has weak ptr to Viewport - Measuring tools + related commands and all trackers now store only a weak_ptr to the Viewport and lock() on demand for usage - LayerHolder and FixedPoint aligner store only a weak_ptr to the Viewport, too - Fixed float/double warning in GrayscaleWindowingSceneTracker

Wish list
=========

* "Start the Viewer with a specific Dicom file and display the
  specific images. For example I start the Viewer with dicomFile and
  open slide1, slide4, slide8, slide12 ?"
  https://groups.google.com/g/orthanc-users/c/6KSe0WEEfco/m/nOIl57EzAAAJ