self_gravity → shamalgs Relation

File in shammodels/sphsrcmodulesself_gravity	Includes file in shamalgs
SGSFMMPlummer.cpp	include / shamalgs / primitives / reduction.hpp
SGSFMMPlummer.cpp	include / shamalgs / primitives / scan_exclusive_sum_in_place.hpp
SGSFMMPlummer.cpp	include / shamalgs / primitives / segmented_sort_in_place.hpp