Merge branch 'master' into updated_vectorisation_tests

.gitignore

examples/main.c

src/Makefile.am

src/cell.c

src/cell.h

src/engine.c

src/gravity/Default/gravity.h

src/gravity/Default/gravity_debug.h

src/gravity/Default/gravity_iact.h

src/gravity/Default/gravity_part.h

src/multipole.h

src/parser.c

src/parser.h

src/runner.c

src/runner_doiact_grav.h

src/space.c

src/swift.h

src/tools.c

tests/Makefile.am

tests/testParser.c