Consolidate save_minimal type trait checks
Consolidate save_minimal type trait checks

relates #85

JosephLaurino/cereal,vcatechnology/cereal,USCiLab/cereal,fawkes74/cereal,fawkes74/cereal,sschaetz/cereal,abutcher-gh/cereal,headupinclouds/cereal,lyager/cereal,USCiLab/cereal,arvidsson/cereal,sschaetz/cereal,guker/cereal,vcatechnology/cereal,jonathan-beard/cereal,jkhoogland/cereal,heamon7/cereal,lyager/cereal,abutcher-gh/cereal,adasworks/cereal,headupinclouds/cereal,jonathan-beard/cereal,arvidsson/cereal,RobertoMalatesta/cereal,syxolk/cereal,guker/cereal,jkhoogland/cereal,RobertoMalatesta/cereal,adasworks/cereal,JosephLaurino/cereal,syxolk/cereal,heamon7/cereal