bugfix: Problems when using identical release names in one booking

Digital Cinema Naming Convention allows identic name of zip-file for different releases e.g.

KDM Studio extends each release with unic random number per release. This allows using multiple releases zip-files with identic NC-letters without problems in the cinema. 
Be sure that releases with different variants (2D/3D/Subtitles etc.) can be embedded in one booking for more time saving.