message: Readme: add link to pre-built binaries
  closes
diff: @@ -5,8 +5,8 @@ GitAhead - Understand Your History
  ==================================
  GitAhead is a graphical Git client designed to help you understand
  -and manage your source code history. It's available as a pre-built
  -binary for Windows, Linux, and macOS, or can be built from source by
  +and manage your source code history. It's available as a [pre-built
  +binary for Windows, Linux, and macOS](https://gitahead.github.io/gitahead.com/), or can be built from source by
  following the directions below.
  How to Get Help
  