#156 check json befor save
#156 check json befor save

moyogo/fontbakery,moyogo/fontbakery,vitalyvolkov/fontbakery,jessamynsmith/fontbakery,davelab6/fontbakery,vitalyvolkov/fontbakery,googlefonts/fontbakery,googlefonts/fontbakery,graphicore/fontbakery,vitalyvolkov/fontbakery,moyogo/fontbakery,googlefonts/fontbakery,graphicore/fontbakery,graphicore/fontbakery