def each_exception
      Dir.chdir(@data_folder)
      Dir.glob("*.exceptions.txt").each do |file|
        if File.open(File.join(@data_folder, file), 'r').read != ''
          yield HTMLValidationResult.load_from_files(file.gsub('.exceptions.txt',''))
        end
      end
    end
def each_exception
      Dir.chdir(@data_folder)
      Dir.glob("*.exceptions.txt").each do |file|
        if File.open(File.join(@data_folder, file), 'r').read != ''
          yield HTMLValidationResult.load_from_files(file.gsub('.exceptions.txt',''))
        end
      end
    end
For each stored exception, yield an HTMLValidationResult object to allow the user to
 call .accept! on the exception if it is OK.