Merge branch 'core_soft' of https://github.com/agiliopadua/lammps into...

Merge branch 'core_soft' of https://github.com/agiliopadua/lammps into combined-user-fep-soft-updates

Resolved Conflicts:
	doc/src/Commands_pair.txt
	doc/src/pair_fep_soft.txt
	doc/src/pair_style.txt
	doc/src/pairs.txt