message: Clean up levels in human formatter
diff: const stream = require('stream')
  const helpers = require('../human/helpers')
  -// Levels
  -const TRACE = 10
  -const DEBUG = 20
  -const INFO = 30
  -const WARN = 40
  -const ERROR = 50
  -const FATAL = 60
  +const LEVELS = {
  + 10: 'trace',
  + 20: 'debug',
  + 30: 'info',
  + 40: 'warn',
  + 50: 'error',
  + 60: 'fatal'
  +}
  /**
  * Writable stream that formats bunyan records written to human readable.
  @@ -23,20 +24,6 @@ class BunyanFormatWritable extends stream.Writable {
  super()
  this.out = out || process.stdout
  this.app = app
  -
  - const levelFromName = {
  - trace: TRACE,
  - debug: DEBUG,
  - info: INFO,
  - warn: WARN,
  - error: ERROR,
  - fatal: FATAL
  - }
  - this.nameFromLevel = {}
  - Object.keys(levelFromName).forEach(name => {
  - const lvl = levelFromName[name]
  - this.nameFromLevel[lvl] = name
  - })
  }
  write (chunk, encoding, cb) {
  @@ -55,7 +42,7 @@ class BunyanFormatWritable extends stream.Writable {
  let message = []
  const c = helpers.color(app)
  - message.push(helpers[this.nameFromLevel[rec.level]](c, rec.msg))
  + message.push(helpers[LEVELS[rec.level]](c, rec.msg))
  if (rec.hint) {
  message = message.concat(helpers.hint(c, rec.hint))
  