Merge branch 'master' into fof_snapshots

configure.ac

doc/RTD/source/HydroSchemes/hydro.dot

doc/RTD/source/HydroSchemes/hydro.png

doc/RTD/source/HydroSchemes/index.rst

doc/RTD/source/ParameterFiles/parameter_description.rst

doc/RTD/source/Planetary/index.rst

doc/RTD/source/Planetary/initial_conditions.rst

doc/RTD/source/Snapshots/index.rst

doc/RTD/source/Task/current_dependencies.rst

doc/RTD/source/Task/grav.dot

doc/RTD/source/Task/grav.png

doc/RTD/source/Task/index.rst

doc/RTD/source/Task/reduced.dot

doc/RTD/source/Task/reduced.png

doc/RTD/source/Task/stars.dot

doc/RTD/source/Task/stars.png

examples/EAGLE_low_z/EAGLE_12/eagle_12.yml

examples/EAGLE_low_z/EAGLE_25/eagle_25.yml

examples/EAGLE_low_z/EAGLE_50/eagle_50.yml

examples/EAGLE_low_z/EAGLE_6/eagle_6.yml