framework to connect and run sequential goroutines.
var ws juzz.Workers
starter := ws.NewStarter("start", start, 1)
composer := ws.NewWorker("compose", compose, 1)
renderer := ws.NewWorker("render", render, 10)
uploader := ws.NewWorker("upload", upload, 1)
starter.Next(composer).Next(renderer).Next(uploader)
ws.Run()
ws.Shutdown()