message: fix link error
diff: //! If you have a use case you are intertested in, you could check the
  //! [examples](./examples), which has all kinds of detailed examples. For example,
  //! If you want to get recently played history, you could check
  -//! [current_user_recently_played](./examples/current_user_recently_played). This is
  +//! [current_user_recently_played](https://github.com/samrayleung/rspotify/blob/master/examples/current_user_recently_played.rs). This is
  //! the example code:
  //! ``` rust
  //! extern crate rspotify;
  