Implementation of the AGNI manybody potential

Small bugfixes and updates

Initializing pointers in VORONOI

Initialize pointers in POEMS

turn on -DLAMMPS_MEMALIGN=64 automatically when USER-INTEL is installed

pair style tersoff/mod/c

Added KOKKOS vashishta

avoid segmentation fault, when creating a LAMMPS instance from the library interface. arg[] may be NULL.