Sink MPI part 1: engine, proxies and strays

...IsolatedGalaxy/IsolatedGalaxy_multi_component/makeDisk.py

examples/SinkParticles/HomogeneousBoxSinkParticles/README

...articles/HomogeneousBoxSinkParticles/getChemistryTable.sh

...les/HomogeneousBoxSinkParticles/getGrackleCoolingTable.sh

examples/SinkParticles/HomogeneousBoxSinkParticles/makeIC.py

...ples/SinkParticles/HomogeneousBoxSinkParticles/mpi_run.sh

...ples/SinkParticles/HomogeneousBoxSinkParticles/params.yml

examples/SinkParticles/HomogeneousBoxSinkParticles/run.sh

src/cell.c

src/cell.h

src/cell_pack.c

src/cell_sinks.h

src/cell_split.c

src/cell_unskip.c

src/cooling/grackle/cooling.c

src/cooling/grackle/cooling.h

src/cooling/none/cooling.h

src/engine.c

src/engine.h

src/engine_config.c