compose files unnecessarily mount host volumes

[larryclaman]

** PLEASE ONLY USE THIS ISSUE TRACKER TO SUBMIT ISSUES WITH THE EXAMPLE VOTING APP **

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Description

The docker-compose.yml (and docker-compose-simple.yml) file use volume mounts for the vote & result apps. While this is something a developer might do while conducting 'inner-loop' debugging, it seems unnecessary and poor practice to have as part of an example of "real code". It also assumes that the source code is on the same machine as the compose file, which really should not be a pre-req. Note that the containers build and execute perfectly fine without the volume mounts

Steps to reproduce the issue, if relevant: see this code:

services: vote: build: ./vote command: python app.py volumes: - ./vote:/app ports: - "5000:80" networks: - front-tier - back-tier

result: build: ./result command: nodemon server.js volumes: - ./result:/app ports: - "5001:80" - "5858:5858" networks: - front-tier - back-tier

[larryclaman]

Created PR #149 with proposed fix

[BretFisher]

We've added a docker-compose.images.yml to do just that... demo the app w/o needing source code downloaded or manual building of images.