Commit secure_download compose and deploy script

[ri-pandey]

The secure_download runs within Docker containers, but the compose file is missing from the repo. This file can be added to the repo, so developers can look at the config before bothering Operations.

The secure_download's deployment script (deploy.sh) should also be committed to the repo.

@rperigo instead of renaming the compose file, you could keep the docker-compose-prod name and keep it within the /secure_download directory.

[rperigo]

I've added an adjusted version of the compose to /secure_download on a new branch (ray_secure_download). There isn't a deploy.sh for this, I simply set the correct UID/GID and such in a .env file and do a docker-compose up. Note: the nginx container is built manually for now for each deployment we have on IU colo nodes - the file has a comment referencing this and it could be moved into the compose directly if desired (and thus use a deploy.sh).

The only Nginx image customization is the creation of the appropriate service account and chowning of files during build.