Fixed a problem with the MoviePlayerDialog

There were some inconsistencies between t-scale of the MoviePlayerDialog and the ImageViewer.
See ticket https://trac.openmicroscopy.org.uk/ome/ticket/12389

To Test:
Have a play with a multi-z/multi-t image and make sure, that the frames shown match your settings in the MoviePlayerDialog. E.g. octopus, user-4, read-only-1/test fff/TestImages/multi-channel-4d-series.ome.tiff