Add docker files and update README

[NdagiStanley]

What does this PR do?

Fixes #46

Description of Task to be completed?

Add docker files and updates the Readme to give instruction on how to run it.

How should this be manually tested?

As outlined in the README:

1. Install docker
2. Run docker-compose up

Note:

I have one line, in the run.sh, what I deem to be the default command for each docker-compose run.

[SendGridDX]

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✅ NdagiStanley
❌ mbernier
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[mbernier]

I believe there should be a docker-compose build step as #2, can you please add that?

[mbernier]

Also, I LOVE that the build runs the tests. That's awesome.
It would be cool to make a note in the README about changing the run.sh file to another script if they want to run that.

[mbernier]

THIS IS AWESOME, btw.

[thinkingserious]

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