Add a mini-howto section for misc. tutorials

[SebastianPrehn]

We have some more niche topics to cover that does not quite fit in with the ordinary sections, and thus it would prove valuable to have a small section that links to very specific topics that we have written a guide for.

My proposal is to add it together with the SOCK5 solution for 2FA SIF access we are making the finishing touches on, and keep it for other niche topics in the future so that we can link it in our support cases, and for curious users to learn about the capabilities of our services.

[aputtu]

Replaces #34054: SOCK5 connection to SIF