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Changes between Version 2 and Version 3 of Ticket #418

-                      v2
+                      v3
 ) phase_space_only
 ) write_phase_space_channels_file (does not make much sense)
+) extra_off_shell_lines (guess, it's obsolete)
+) splitting_depth (covered by new PS algorithm??)
+) exchange_lines = phs_t_channel ???
+) single/double_off_shell_branchings/decays
+) massive_fsr (still necessary?)
+) threshold_mass   = phs_threshold_s ??
+) threshold_mass_t = phs_threshold_t ??
+) default_jet_cut/default_mass_cut ~ phs_m_scale ??
+) default_q_cut ~ phs_q_scale ??
+) default_e_cut ~ phs_e_scale ??