* Update Cargo.toml for Rocket `master`
* Prepare library for Rocket 0.4
TODO: check line 62 in `fairing.rs` to find better way than unwrapping
* Bump minimum nightly for Rocket 0.4
* Bump Rocket, Rust version and remove impl trait flag
* Seems to build now
* Ignore Rocket documentation errors
* Update travis script
* Increase nightly version by a day
* Bump again