Docker support

[cgmartin]

Adds a Dockerfile and npm scripts to build/run the quickstart with Docker.

Usage:

• To build and run the quickstart in a Docker container: npm run docker

Sharing this primarily as an example, since Docker image building with npm postinstall scripts is not always straightforward.

Docker has also been helpful in troubleshooting Linux-OS related issues in lite-server.

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[cgmartin]

I signed it!

[googlebot]

CLAs look good, thanks!

[johnpapa]

Thanks for this @cgmartin !

[wardbell]

LGTM. Awaiting confirmation of CLA

[cgmartin]

googlebot

CLAs look good, thanks!

Was there anything else you needed from me for the CLA? (this is my first experience with Google's CLA)

[wardbell]

No, @cgmartin. It's just me. I see that you were approved since i last looked. I'll accept this shortly. Thanks!

[wardbell]

Merged at last. Thanks Chris.