feat: upgrade herokuish
feat: upgrade herokuish

This enables herokuish to be installed when moby-engine is the docker-engine that is available.

dokku/dokku,claytonbrown/dokku,dokku/dokku,progrium/dokku,progrium/dokku,progrium/dokku,claytonbrown/dokku,claytonbrown/dokku,progrium/dokku,claytonbrown/dokku,dokku/dokku,progrium/dokku,dokku/dokku,dokku/dokku,progrium/dokku,claytonbrown/dokku,dokku/dokku,claytonbrown/dokku,dokku/dokku,claytonbrown/dokku,dokku/dokku,claytonbrown/dokku,progrium/dokku,progrium/dokku