Portals server client loader

[MKLepium]

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[jspenger]

Just some smaller notes, can be merged after changes.

Here are some additional comments:
We should have some scripts that make it easy to run the VLDB demo. I suggest creating a sub-directory scenario1 in the vldb-demo repo: https://github.com/portals-project/vldb2023demo. Where these scripts are included, and should likely have the following:

• A script that installs everything that is necessary.
• A script that starts minikube and starts docker.
• A script that launches the kubernetes deployment.
• A script that, when started, starts observing the logs of the kubernetes deployment; so that we can inspect what is happening on the server.
• A script that cleans up the kubernetes deployment / removes it.
• A script that removes the produced docker containers, cleans it up.

With these scripts, you should be able to easier describe how to run the entire demo from start to finish. Note that it should be interactive, and the attendant should see things happening. That is why we also would like to inspect the logs, etc.

Note that you might need to set the portals core repo as a sub-repository in the vldb demo repository.