Close All Windows WindowCloseBehaviour

## Feature Request

It would be great to have a WindowCloseBehaviour, that closes all Windows currently open, like any Popup opened.
When for example the window which has the CloseAllWindows behaviour set (this could be a main window) closes all the opened Popups with it (for example some Settings Popup or something).

## Implement Suggestion

It would be great if this could be done in the WindowCloseBehaviour as another close behaviour for a window.
It could look at the end like this:
```rust
use dioxus::desktop::WindowCloseBehaviour;

let config = dioxus::desktop::Config::new().with_close_behaviour(WindowCloseBehaviour::CloseAllWindows);

// Launch the app with the custom menu
LaunchBuilder::new().with_cfg(config).launch(App)
```