def find_fields name
      res = {}
      @lines.each do | line |
        value = line.scan(/###{name}=<(.*)>/)
        if value[0]
          str = value[0][0]
          # p str
          v = VcfHeaderParser.parse_field(line,@debug)
          id = v['ID']
          res[id] = v
        end
      end
      # p res
      res
    end
def find_fields name
      res = {}
      @lines.each do | line |
        value = line.scan(/###{name}=<(.*)>/)
        if value[0]
          str = value[0][0]
          # p str
          v = VcfHeaderParser.parse_field(line,@debug)
          id = v['ID']
          res[id] = v
        end
      end
      # p res
      res
    end
Look for all the lines that match the field name and return
 a hash of hashes. An empty hash is returned when there are
 no matches.