eljost/pysisyphus: Bugfixes & expanded documentation

Bugfixes Added missing files for worked example of trispericyclic reaction in examples/complex/08_trispericyclic/ Initial displacement from TS using 3rd derivatives of the energy (displ: energy_cubic) should now be more reliable. The resulting HDF5 dump can be reused via the displ_third_h5: [path to hdf5] option (see the IRC documentation) Miscellaneous Improved calculator documentation for ORCA, XTB, Turbomole and Calculators in general Added Citation.cff Updated Turbomole tests and added Turbomole Growing String examples using the native pysisyphus calculator as well as the QCEngine wrappe