Dynamically change multiSelect

I have two views with ng-grid and they're almost the same except the fact that one should allow multiSelect and another shouldn't.
I can render it two times with different options but since the grid is quite huge it takes long time.
It would be better to be able to dynamically change its behavior; however now configuration is read just once — before rendering — and it's impossible to change it afterwards.

I made some changes, so now it behaves exactly like the data parameter: you can either pass a value or a string. In  case of the string we simply bind and watch it.