forpro-vis/wp2: Display Toast message when Flashcard is created in lecturer view

[becknik]

Currently, when Saveing a new Flashcard, the AddFlashcard component disappears and a new FlashcardView appears. Since the two components look pretty much the same, I'd propose adding some visual hint that the flashcard has been added to the relay store.

This could be archived by using a simple "Success Toast", highlighting the newly created FlashcardView component or something more creative. Just let it be something visually more appealing as a native browser toast ;)

[BabaHonegga]

Implemented this function. Maybe needs clearer names.