Fixes issue 222 (crash on adding columns to a gridview with no sets)
Fixes issue 222 (crash on adding columns to a gridview with no sets)

KasaiDot/dwarftherapist,KasaiDot/dwarftherapist,tectronics/dwarftherapist,dozedoff/dwarftherapist,KasaiDot/dwarftherapist,dozedoff/dwarftherapist,consultorio-molinari/splintermind-attributes,montanalow/dwarftherapist,tectronics/dwarftherapist,NGUYENVanTri/dwarftherapist,montanalow/dwarftherapist,consultorio-molinari/splintermind-attributes,tectronics/dwarftherapist,Ofunniku/dwarftherapist,dozedoff/dwarftherapist,PixelPicks/dwarftherapist,dozedoff/dwarftherapist,montanalow/dwarftherapist,consultorio-molinari/splintermind-attributes,PixelPicks/dwarftherapist,tectronics/dwarftherapist,Ofunniku/dwarftherapist,NGUYENVanTri/dwarftherapist,consultorio-molinari/splintermind-attributes,KasaiDot/dwarftherapist,NGUYENVanTri/dwarftherapist,walkerp1/dwarftherapist,PixelPicks/dwarftherapist,PixelPicks/dwarftherapist,walkerp1/dwarftherapist,Ofunniku/dwarftherapist,montanalow/dwarftherapist,Ofunniku/dwarftherapist,walkerp1/dwarftherapist,NGUYENVanTri/dwarftherapist,walkerp1/dwarftherapist