Add event to onSelect function

[ssword]

Thanks for the great Selection Menu you have created. I almost give up on my project due to Material UI compatibility problem.
I am currently trying to add SHIFT key support. But I can't find SHIFT keypress without event. I know that SHIFT key support is on your TODO list. It will be convenient if you can expose event to onSelct or onChange so that we can customize the KEY PRESS behavior.