when the end-user installs on an arch/os that doesn't have packaged binaries, a nice message should be given

[avh4]

elm-platform current uses a message like this:

var errorMessage = "Unfortunately, there are no elm-format " + packageInfo.version + " binaries available for your operating system and architecture.\n\nIf you would like to build elm-format from source, there are instructions at https://github.com/avh4/elm-format#building-from-source\n";