Added spec test to cover optionsText parameter accepting a function (cherry picked from commit 3d23c9a85b4d87c9c4fe84a1247c39c54fd7a7b4)
Added spec test to cover optionsText parameter accepting a function
(cherry picked from commit 3d23c9a85b4d87c9c4fe84a1247c39c54fd7a7b4)

youprofit/knockout,getshuvo/knockout,JesseQin/knockout,pianove/knockout,DekeYan/knockout,pianove/knockout,ErikSchierboom/knockout,getshuvo/knockout,moonpyk/knockout,gwokudasam/knockout,mattbalmer/knuckles,moonpyk/knockout,martijnwetering/knockout,bago/knockout,stonegithubs/knockout,youprofit/knockout,brianmhunt/knockout,DekeYan/knockout,cgourlay/knockout,Sir0xb/knockout,JesseQin/knockout,Sir0xb/knockout,martijnwetering/knockout,xeronith/knockout,stonegithubs/knockout,ErikSchierboom/knockout,hitesh97/knockout,brianmhunt/knockout,gwokudasam/knockout,bago/knockout,skyh/knockout,skyh/knockout,cgourlay/knockout,hitesh97/knockout,mattbalmer/knuckles,xeronith/knockout