Merge branch 'master' of gitlab.cosma.dur.ac.uk:swift/swiftsim

configure.ac

examples/ExternalPointMass/energy_plot.py

examples/main.c

src/active.h

src/cell.c

src/cell.h

src/drift.h

src/engine.c

src/engine.h

src/gravity/Default/gravity.h

src/kick.h

src/runner.c

src/space.c

src/space.h

src/stars/Default/star_part.h