old_contents: # The supported extensions, as defined by https://github.com/github/markup
  supported_extensions = ['.md', '.markdown']
  
  # The default filenames when no file is provided
  default_filenames = map(lambda ext: 'README' + ext, supported_extensions)
  
new_contents: # The supported extensions, as defined by https://github.com/github/markup
  supported_extensions = [
      '.markdown', '.mdown', '.mkdn', '.md',
      '.textile',
      '.rdoc',
      '.org',
      '.creole',
      '.mediawiki', '.wiki',
      '.rst',
      '.asciidoc', '.adoc', '.asc',
      '.pod',
  ]
  
  
  # The default filenames when no file is provided
  default_filenames = map(lambda ext: 'README' + ext, supported_extensions)
  
subject: Add the GitHub-supported format extensions.