- Remove GDM and Firstboot `.sed' translation files.  
    
    - Add GDM and Firstboot `.png.sh' translation files.  
    
    - Inside GDM: instead of using Img/ and Tgz/ directories to store
      images and tar.gz files respectively, we save images temporarally in
      order to produce tar.gz files directly outside Tgz directory. So, we
      no longer use neither Img/ nor Tgz/ directories.