Relocate release notes files inside the repository.
    
    - Previously, release notes source files were stored at
      Artworks/Documentation/Repository/UserGuide/Asciidoc/Distro/
      directory. Now release notes source files are stored at
      Artworks/Themes/Models/Release_notes/ and the
      Artworks/Documentation/Repository/UserGuide/Asciidoc/Distro/
      directory was removed. The Artworks/Documentation/Repository
      directory shouldn't have any documentation unrelated to repository
      matters properly.
    
    - Previously, release notes translation files were stored at
      Artworks/Locales directory. This contradicts the current
      implementation of locale module. Now, relase notes translation files
      are stored at Artworks/Themes/Models/Release_notes/Locales directory
      which complies with the current implementation of locale module. The
      release notes translation files inside Artworks/Locales directory
      were removed.