Merge branch 'generic-avg-output' into 'master'

ProcessLib/LargeDeformation/LargeDeformationProcess.cpp

ProcessLib/Output/CellAverageAlgorithm.h

ProcessLib/Output/CellAverageData.cpp

ProcessLib/Output/CellAverageData.h

ProcessLib/Process.cpp

ProcessLib/Process.h

ProcessLib/SmallDeformation/SmallDeformationProcess.cpp

ProcessLib/TH2M/TH2MFEM-impl.h

ProcessLib/TH2M/TH2MProcess.cpp

ProcessLib/TH2M/TH2MProcessData.h

...ThermoRichardsMechanics/ThermoRichardsMechanicsFEM-impl.h

...hermoRichardsMechanics/ThermoRichardsMechanicsProcess.cpp

...rmoRichardsMechanics/ThermoRichardsMechanicsProcessData.h

...ichardsMechanics/RichardsFlow2D/RichardsFlow_2d_small.prj

.../RichardsFlow2D/RichardsFlow_2d_small_ts_0_t_0.000000.vtu

...ardsFlow2D/RichardsFlow_2d_small_ts_104_t_2000.000000.vtu

...chardsFlow2D/RichardsFlow_2d_small_ts_19_t_318.000000.vtu

.../RichardsFlow2D/RichardsFlow_2d_small_ts_1_t_1.000000.vtu

...chardsFlow2D/RichardsFlow_2d_small_ts_29_t_518.000000.vtu

.../RichardsFlow2D/RichardsFlow_2d_small_ts_2_t_3.000000.vtu