Merge branch 'master' into rebuild_criteria

.gitignore

README

examples/EAGLE_12/eagle_12.yml

examples/UniformDMBox/uniformBox.yml

examples/main.c

examples/parameter_example.yml

examples/plot_gravity_checks.py

src/Makefile.am

src/cell.c

src/cell.h

src/collectgroup.c

src/collectgroup.h

src/engine.c

src/engine.h

src/gravity.c

src/gravity_properties.c

src/gravity_properties.h

src/kernel_gravity.h

src/multipole.h

src/runner_doiact.h