Update image directory used inside documentation.
    
    - Previously, when documentation was rendered using the render module,
      the Images link pointed to Artworks/Icons/Webenv directory. However,
      the current implementation of render module stores final images in
      the Artworks/Icons/Webenv/Final directory. This update changes the
      asciidoc_setXhtmlRendition function to use
      Artworks/Icons/Webenv/Final directory as source location instead of
      Artworks/Icons/Webenv directory.
    
    - Previously, when documentation was rendered using the render module,
      callout images were stored inside Artworks/Icons/Webenv/Callouts
      directory. In order to reuse the Artwork/Icons/Webenv/Final
      directory, callouts were moved out of Callouts directory and stored
      directly inside Artwork/Icons/Webenv/. This update changes the
      callout.graphics.path definition inside XSL files to use callout
      images stored inside Artwork/Icons/Webenv/Final directory instead of
      Artwork/Icons/Webenv/Callouts directory. As consequence, the
      Artworks/Icons/Webenv/Callouts directory was removed.