[options.length=30] (number): 최대 문자열 길이 (omission 길이 포함)
[options.omission='...'] (string): 생략된 영역을 나타내는 문자열
[options.separator] (RegExp|string): 문자열을 잘라낼 구분자

truncate('hi-diddly-ho there, neighborino'); // 'hi-diddly-ho there, neighbo...'

truncate('hi-diddly-ho there, neighborino', {
  length: 24,
  sperator: ' ',
}); 'hi-diddly-ho there,...'

truncate('hi-diddly-ho there, neighborino', {
  omission: ' [...]'
  length: 24,
  separator: /,? +/
}); 'hi-diddly-ho there [...]'