Toast toasts [to a st]ellar UX
As mentioned in !35 (merged) (here, and here), we want to implement a Toaster to give the user some subtle feedback, particularly when downloading CPN/CPPN and LTS exports.
As implementing a top level toaster in the current Angular+React state may cause unforeseen issues, we move this feature request into an issue to be addressed, once AngularJS has successfully been yote.