Toaster 5.0 changes

Toaster functionality remains the same in in Blueprint v5, but there are some name changes. As part of the effort to drop the "I" prefix from all interface names, IToaster is now simply Toaster. Toaster, which implements this interface in v5, is now OverlayToaster in v5. This more explicit name signifies that it is a certain kind of toaster, one that presents the toast messages in an overlay on top of other parts of the application (for now, it is the only available toaster implementation).

Here is the migration you can do in v4 before upgrading to v5:

• Toaster -> OverlayToaster
• IToasterProps -> OverlayToasterProps
• IToastProps -> ToastProps
• IToaster -> ToasterInstance

In v5, ToasterInstance will remain available but it will be deprecated in favor of the more straightforward Toaster type.