never did move these around to match the .cc
template_binning, and make/load_templates; do_by_means to turn off that thing; make sure to update weighting pars when changing phi_exp.
poisson_n1vs -> True
fix template_fn default and prints.
Respect sample_only in fit_envelopes; only do the old stuff when do_by_means.
Need to run fit_envelopes and fs, at least to get g_dphi/dz and f_dz; don't book histos not used; specify template range in cfg; make_2v_toy.