Update trunk/Identity/Models/Themes/Default directory structure:
    
        - Move Default/Promo/Stationery/Posters directory structure to
          Default/Posters directory structure. At this moment there is no
          other stationery stuff to produce (except Media which is inside
          Distro for reusing the release schema). Since there is no other
          stationery stuff to produce, the path information was reduced.