Add puppet mixins

[su-chang]

Divide all methods which extends from wechaty-puppet into different entities.

• [x] implement puppet-mixin
  • [x] contact-self #289
  • [x] contact #290
  • [x] conversation #286
  • [x] friendship #291
  • [x] message #297
  • [x] room #298
  • [x] tag #287
• [x] adapt these methods to puppet-whatsapp #300