Add removedToast observable

[CaselIT]

First of all thanks for this useful library!

It would be nice to have an observable in the ToasterService which notifies when a toast has been removed, regardless of the reason. It would the opposite of the addToast observable

I you like I could make a pr with this feature.

[CaselIT]

Any update @Stabzs ?

[Stabzs]

Thanks for the feedback and the request!

Absolutely, I can see the value in this. What would be broadcasted would be the toastId and the containerId. There is obviously a case where multiple events would be broadcasted for a toast that exists in multiple containers. I can look at adding this soon.

[CaselIT]

Great, Thanks.

[Stabzs]

@CaselIT I haven't had time to get to this yet. If you are interested in creating a PR with tests, it would definitely help get this completed sooner :). Else I'll get to it when I can.

[CaselIT]

I'll look into it.
Thanks

[Stabzs]

Since there hasn't been a lot of traction on this particular request, it doesn't seem to be that large of a demand. Closing.