message: remove comments from doc
diff: //!
  //! Add this to your `Cargo.toml`:
  //!
  -// //! ```toml
  -// //! [dependencies]
  -// //! argmin = "0.1.8"
  -// //! ```
  //! ```toml
  //! [dependencies]
  //! argmin = { git = "https://github.com/argmin-rs/argmin.git", branch = "master"}
  //!
  //! There are additional features which can be activated in `Cargo.toml`:
  //!
  -// //! argmin = { version = "0.1.8", features = ["ctrlc", "ndarrayl"] }
  //! ```toml
  //! [dependencies]
  //! argmin = { git = "https://github.com/argmin-rs/argmin.git",
  