def yamline_delete!(lines = nil)
      lines = file_lines unless lines
      return unless lines
      lines_readed = yamline_read(lines, false)
      lines_readed.each {|lr| lines.delete(lr) } if lines_readed
      save_file(lines)
    end
def yamline_delete!(lines = nil)
      lines = file_lines unless lines
      return unless lines
      lines_readed = yamline_read(lines, false)
      lines_readed.each {|lr| lines.delete(lr) } if lines_readed
      save_file(lines)
    end
Finds and deletes formatted line/lines from supplied
file/files. if formetted line is not uniq it deletes all of them.
  a.yamline_set(:file => 'test.txt')
  a.yamline_delete!