fire minimizer - NEB

Please keep the list in the loop.

If you look at examples/neb and run
in.neb.hop2 (which uses fire) then files
like log.lammps.0 will be produced.
Those are for individual replicas.

And you will see lines like
Minimization stats:
Stopping criterion = force tolerance
after each NEB stage.

That's what tells you why the minimizer