Merge branch 'master' into delayed_foreign_allocation

configure.ac

doc/RTD/source/ParameterFiles/index.rst

doc/RTD/source/ParameterFiles/output_selection.rst

doc/RTD/source/Snapshots/index.rst

doc/RTD/source/SubgridModels/EAGLE/index.rst

examples/EAGLE_25/run.sh

examples/main.c

examples/parameter_example.yml

src/cooling/EAGLE/cooling.c

src/dimension.h

src/engine.c

src/engine.h

src/engine_maketasks.c

src/hydro_properties.c

src/parallel_io.c

src/partition.c

src/runner.c

src/serial_io.c

src/single_io.c

src/space.c