Use latest Shiny Server build, and Add docker-compose file

[jglev]

Thank you for your work on this project!

I see that in #36, @wch mentioned that this project is not still active. Even with that in mind, I'm wondering whether you might still welcome this Pull Request. This PR does three things:

1. Explicitly note in the Dockerfile where to find Shiny Server installation instructions (https://www.rstudio.com/products/shiny/download-server/).
2. Update the Dockerfile to use the latest version of Shiny Server, from the instructions at the above URL.
3. Add a docker-compose.yml file, facilitating use in larger Docker networks.

Even if this project is no longer maintained, its presence here and on Docker Hub helped me to get up and running more quickly just now. These changes could make it easier for other future users of this repo. to keep their installs up-to-date, as well.

Thank you for your consideration!

[cboettig]

LGTM

[eddelbuettel]

I might prefer the README.md to show docker-compose as an option rarther than the only choice as that would be a bit more in line with the rest of our setups.

[pieterlukasse]

this is great, thanks. I do agree with @eddelbuettel that it would be nice to keep the plain docker documentation as well. So perhaps split into 2 sections? The old one and a new one for docker-compose.

[jglev]

Thank you all! I'm happy to split the Readme into two sub-sections. I'm away from my computer most of today, but I look forward to doing so either this evening or Thursday (Given the US holiday tomorrow). I'd also like to add slightly to the documentation re: mountpoints, as I think about it more.

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On July 3, 2018 8:15:31 AM EDT, pieterlukasse ***@***.***> wrote: pieterlukasse commented on this pull request. this is great, thanks. I do agree with @eddelbuettel that it would be nice to keep the plain docker documentation as well. So perhaps split into 2 sections? The old one and a new one for docker-compose. -- You are receiving this because you authored the thread. Reply to this email directly or view it on GitHub: #37 (review)

[jglev]

I'm sorry for the delay with this, but am excited to have just pushed commits that:

1. answer @eddelbuettel and @pieterlukasse's comments above re: retaining the original Docker use instructions,
2. add additional documentation for the Dockerfile for building with a custom configuration file, and
3. add additional documentation for using custom mountpoints and a persistent volume for app logs using the example docker-compose file.

[cboettig]

Thanks for this, LGTM. Will go ahead and merge later this week if there are no further comments etc