Commented Feature: Implement Create Mute [2213]

Implement the new Mute endpoint: [https://dev.twitter.com/docs/api/1.1/post/mutes/users/create](https://dev.twitter.com/docs/api/1.1/post/mutes/users/create)
Comments: Associated with changeset 42702: Version 0.9.7.0
- Implemented Mute User