FSI SU2/CalculiX: Restructure run scripts to remove tmux

[MakisH]

We are currently triggering tmux from inside the tutorial's run scripts, as e.g. here:
https://github.com/precice/tutorials/blob/master/FSI/flap_perp/SU2-CalculiX/runTutorial_parallel.sh

This is inconsistent with the rest of our cases and probably difficult for most new users to follow. We should restructure the tutorial to have a runFluid (also in parallel) and a runSolid script that can be started in separate terminals and are easier to follow.

We should also add an Allrun and an Allclean script, currently missing.

[IshaanDesai]

Closed in #100