fix h2 distribution in MultiphaseNonReflectingOutflowBCAlgorithm; fix negative phi in MultiphaseVelocityBCAlgorithm and in MultiphaseSimpleVelocityBaseExternalPressureLBMKernel; add unit test für FineToCoarseVectorConnector; redesign nozzle simulation setup

# Conflicts:
# apps/cpu/Applications.cmake
# apps/cpu/ViskomatXL/viskomat.cfg

Corrected stress correction and a different way to implement the force externally from the kernel. Initial conditions for jet.

corrects pressure update in MultiphaseTwoPhaseFieldsPressureFilterLBMKernel, MultiphasePressureFilterCompressibleAirLBMKernel and MultiphasePressureFilterCompressibleAirLBMKernel. MultiphasePressureFilterCompressibleAirLBMKernel is not yet different from MultiphasePressureFilterCompressibleAirLBMKernel and hence not yet compressible.