Code formatting

examples/main.c

src/align.h

src/common_io.c

src/engine.c

src/parallel_io.c

src/partition.c

src/proxy.c

src/restart.c

src/runner_doiact_fft.c

src/runner_doiact_grav.h

src/scheduler.c

src/single_io.c

src/space.c