Add partitioned pipe tutorial (moved from openfoam-adapter)

[MakisH]

This moves the fluid-fluid coupling tutorials from the OpenFOAM adapter.

Reviewers:

• @uekerman please have a look at the README. I used the same precice-config.xml as with the previous 2xpimpleFoam (the compressible one was using parallel-implicit and had more relaxed convergence measures).

Before merging:

• ℹ️ Currently depends on Restructure runscripts and related resources #181, will change the target branch to develop later.

After merging:

• Remove cases from openfoam-adapter (opened PR Remove tutorials openfoam-adapter#160)
• Add an entry in the tutorials sidebar

[uekerman]

README looks good. Only minor things below.
You added four pngs for the pipe. On purpose?

[MakisH]

You added four pngs for the pipe. On purpose?

Yes, to showcase that all these combinations work. Would there be a reason to remove them? (details, but let's decide)

[uekerman]

Yes, to showcase that all these combinations work. Would there be a reason to remove them? (details, but let's decide)

If we don't show them somewhere, we might forget why we have them.

[MakisH]

Yes, to showcase that all these combinations work. Would there be a reason to remove them? (details, but let's decide)

If we don't show them somewhere, we might forget why we have them.

Good point, I removed them.