Merge branch 'feedback' into 'master'

.gitignore

configure.ac

doc/RTD/source/Task/adding_your_own.rst

doc/RTD/source/Task/index.rst

doc/RTD/source/index.rst

examples/analyse_tasks.py

examples/main.c

examples/parameter_example.yml

examples/plot_tasks.py

src/Makefile.am

src/active.h

src/cell.c

src/cell.h

src/common_io.c

src/common_io.h

src/engine.c

src/engine.h

src/kick.h

src/parallel_io.c

src/part.c