Provide TU Wien SP configuration as example

[max-moser]

Idea

We're using SATOSA as part of our authentication pipeline for the service provider (SP) TU Wien Research Data, our institutional research data repository.
This SP has been registered into the Austrian ACOnet federation, and also the eduGAIN interfederation.
We're utilizing the interfederation metadata to allow login with many identity providers (IdP) globally.

I figured that this setup may make for a decent example, especially given that we improved the configuration together with Peter Brand from ACOnet not that long ago.

I intend to be touching up some of the documentation pages to refer to these example configurations, as well as our services in the TU Wien GitLab instance:

• SATOSA setup
• Simple custom discovery service

Checklist

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