Replace localStorage with Firebase for storing decks and runs

[cvharris]

Right now Redux subscribes to all store changes and saves the entire store in the user's localStorage on the browser. This is not a good persistance method and prevents us from sharing decks to other Etude users.

1. Redux should no longer save the entire store in its subscription
2. Instead, each action has its own side-effects to save/get data saved in Firestore
3. Add Firebase project (collaborators have project access) to Etude
4. Replace all CRUD for Decks and Practice Runs with Firebase