Extend warning for not readable configuration file. unify mains accordingly.

apps/cpu/GyroidsRow/GyroidsRow.cpp

apps/cpu/LaminarPipeFlow/LaminarPipeFlow.cpp

apps/cpu/LaminarPlaneFlow/LaminarPlaneFlow.cpp

apps/cpu/LidDrivenCavity/LidDrivenCavity.cpp

apps/gpu/ActuatorLine/ActuatorLine.cpp

apps/gpu/DrivenCavity/DrivenCavity.cpp

apps/gpu/DrivenCavityMultiGPU/DrivenCavityMultiGPU.cpp

apps/gpu/SphereInChannel/SphereInChannel.cpp

apps/gpu/SphereMultiGPU/SphereMultiGPU.cpp

apps/gpu/TGV_3D/TGV_3D.cpp

src/basics/config/ConfigurationFile.cpp

src/basics/config/ConfigurationFile.h