Use -p instead of --port and set a more useful tag

[simonw]

I got an error with --port which was fixed by switching to -p:

multi-process-container-lazy-solution % docker run --port 5000:8080 --rm multi-process-container-lazy-solution
unknown flag: --port
See 'docker run --help'.
multi-process-container-lazy-solution % docker run -p 5000:8080 --rm multi-process-container-lazy-solution
 * Environment: production
   WARNING: This is a development server. Do not use it in a production deployment.
   Use a production WSGI server instead.
 * Debug mode: off
 * Running on http://127.0.0.1:8081/ (Press CTRL+C to quit)

I think multi-process-container-lazy-solution is a better tag than foo because I often forget what containers I've built on my system, so I like to see memorable names in docker images.