Merge branch 'master' into star_particles

.gitignore

configure.ac

examples/CoolingHalo/cooling_halo.yml

examples/CoolingHaloWithSpin/cooling_halo.yml

examples/HydrostaticHalo/hydrostatic.yml

examples/main.c

examples/parameter_example.yml

src/Makefile.am

src/active.h

src/cell.c

src/cell.h

src/dump.c

src/dump.h

src/engine.c

src/engine.h

src/potential.h

src/potential/disc_patch/potential.h

src/potential/isothermal/potential.h

src/potential/none/potential.h

src/potential/point_mass/potential.h