Merge branch 'master' of ssh://git.mpi-cbg.de/openfpm/openfpm_numerics

src/CMakeLists.txt

src/FiniteDifference/util/common.hpp

src/initialize/initialize_wrapper_cpu.cpp

src/initialize/initialize_wrapper_cuda.cu

src/interpolation/interpolation.hpp

src/interpolation/interpolation_unit_tests.cpp

src/main.cpp