rfc5424 structured data parsing

[opichals]

By default the logger executable sends some RFC5424 structured data fields (see http://kerolasa.github.io/logger.html for details) which seem not to be recognized by the parser. Notice especially the 'messageandheader` property.

logger "test message from logger"

results in the following parser output

{ date: '2020-02-02T12:55:52.333Z',
  host: 'nuc',
  message:
   'tzKnown="1" isSynced="1" syncAccuracy="77000"] test message from logger',
  protocol: 'IPv4',
  originalMessage:
   '<13>1 2020-02-02T13:55:52.332998+01:00 nuc standa - - [timeQuality tzKnown="1" isSynced="1" syncAccuracy="77000"] test message from logger',
  pri: '<13>',
  prival: 13,
  facilityval: 1,
  levelval: 5,
  facility: 'user',
  level: 'notice',
  version: 1,
  type: 'RFC5424',
  ts: '2020-02-02T12:55:52.332Z',
  appName: 'standa',
  pid: '-',
  messageid: '-',
  structuredData: [],
  chain: [],
  fields: [],
  header:
   '<13>1 2020-02-02T13:55:52.332998+01:00 nuc standa - - [timeQuality ' }