docs(ngModel.NgModelController) use `$evalAsync` instead of `$apply` for event handling
docs(ngModel.NgModelController) use `$evalAsync` instead of `$apply` for event handling

Have the apply called safely during events by using `$evalAsync` rather than `$apply`
This will help ensure that an apply for a user directive is not called during a digest cycle.

Closes #9891

ggershoni/angular.js,ggershoni/angular.js,ggershoni/angular.js,ggershoni/angular.js