Merge branch 'master' into doself2-vectorisation

examples/DiscPatch/HydroStatic/plot.py

examples/analyse_tasks.py

examples/analyse_tasks_MPI.py

examples/parameter_example.yml

examples/plot_tasks.py

examples/plot_tasks_MPI.py

examples/process_plot_tasks

examples/process_plot_tasks_MPI

src/Makefile.am

src/cell.c

src/const.h

src/engine.c

src/hydro/Gizmo/hydro.h

src/hydro/Gizmo/hydro_gradients.h

src/hydro/Gizmo/hydro_gradients_gizmo.h

src/hydro/Gizmo/hydro_iact.h

src/hydro/Gizmo/hydro_io.h

src/hydro/Gizmo/hydro_part.h

src/hydro/Gizmo/hydro_slope_limiters_face.h

src/hydro/Gizmo/hydro_unphysical.h