message: better resolution for gitter badge
diff: [![Build Status](https://travis-ci.org/input-output-hk/rust-cardano.svg?branch=master)](https://travis-ci.org/input-output-hk/rust-cardano)
  [![Build status](https://ci.appveyor.com/api/projects/status/owl4qu760o6r0g1o?svg=true)](https://ci.appveyor.com/project/input-output-hk/rust-cardano)
  -[![Gitter chat](https://badges.gitter.im/gitterHQ/gitter.png)](https://gitter.im/input-output-hk/Cardano-Rust)
  +[![Gitter chat](https://img.shields.io/badge/gitter-join%20chat%20%E2%86%92-brightgreen.svg)](https://gitter.im/input-output-hk/Cardano-Rust)
  # rust implementation of cardano wallet and crypto
  