another mistake corrected... still not working
....
Merge branch 'derivatives' of https://github.com/akandra/mdhag into derivatives

Conflicts:
	pes_fitting_programs/Fit_with_static_lattice/derivatives/EMTparms_class_v2.f95
	pes_fitting_programs/Fit_with_static_lattice/derivatives/fit_debug.out
	pes_fitting_programs/Fit_with_static_lattice/derivatives/nllsq.dbl.f
Derivatives finally implemented.