message: Change the docs link to refer to docs.rs
diff: [![Build Status](https://img.shields.io/travis/aldanor/hdf5-rs.svg)](https://travis-ci.org/aldanor/hdf5-rs) [![Appveyor Build Status](https://img.shields.io/appveyor/ci/aldanor/hdf5-rs.svg)](https://ci.appveyor.com/project/aldanor/hdf5-rs)
  -[Documentation](http://aldanor.github.io/hdf5-rs/h5)
  +[Documentation](https://docs.rs/crate/hdf5-rs)
  [Changelog](https://github.com/aldanor/hdf5-rs/blob/master/CHANGELOG.md)
  Thread-safe Rust bindings and high-level wrappers for the HDF5 library API.
  