lat_phys_ratios: add PDG/FLAG used for lattice 2014 talk
lat_phys_ratios: updated physical inputs with latest values from PDG/FLAG
lat_phys_ratios: add support for isospin symmetric values to phys_ratios
phys_ratios: use the option stingsAsFactors=FALSE
lat_phys_ratios: inconsequential change to phys.dat
plot_mpcac_v_kappa: update comments
phys_ratios: add functionality to compute ratios combining values from all kinds of sources (for now, pdg, flag, isospin symmetric limit)
ratios_and_interpolations: add a recomputation of m_K_ov_f_K to take into account the strange mass from m_K_ov_m_pi and add extrapolations for f_D_ov_f_K and f_Ds_ov_f_K