better service orchestration (ability to delete apps and set env vars)

[Ivshti]

A bunch of architectural improvements to bring the following improvements:

• ability to delete apps
• ability to set env vars (secrets)
• running reverse proxy server on all swarm nodes, allowing for load balancing

To implement:

• [ ] rename beamup-sync-swarm to beamup-orchestrate
• [ ] beamup-orchestrate to receive the app name and env vars (secrets); that'd be easy as we have $APP here https://github.com/Stremio/stremio-beamup/blob/master/dokku-plugins/beamup-trigger-swarm-sync/post-deploy#L13 ; it will need it so that it only updates the app rather than triggering a swarm deploy; we need the env vars so we can set them for that service
• [ ] configured environment variables to work
• [ ] auto-configure NGINX/stremio-addon-proxy on BOTH swarm nodes: this can work through a container that auto-configures itself in a way similar to nginx-proxy, but based on the Docker /services endpoint
• [ ] Cloudflare err handling: if we fail adding the record, fail from beamup-orchestrate, which will propagate the error through ssh back to the deployer, so that the user will know deployment failed
• [ ] deleting apps to work, again through beamup-orchestrate
  • btw dokku apps:destroy needs a tty: except with --force
  • how to delete from a private docker registry? rm -rf /var/lib/registry/docker/registry/v2/repositories/dokku/ivshti_topmovies/?