Some improvement suggestions for newbie reading the client tutorials (section 5 to 8)

https://www.apollographql.com/docs/tutorial/client.html#react-apollo
- no react and react-dom imports
- where did Pages component came from?

https://www.apollographql.com/docs/tutorial/queries.html#fragments
- LAUNCH_TILE_DATA should be above GET_LAUNCHES
- please mention src/pages/launch.js

https://www.apollographql.com/docs/tutorial/mutations.html#authenticate
- where did resolver and typeDefs came from?

https://www.apollographql.com/docs/tutorial/local-state.html#local-query
- where did injectStyles() came from?

https://www.apollographql.com/docs/tutorial/local-state.html#virtual-fields
- where did GET_CART_ITEMS came from?

https://www.apollographql.com/docs/tutorial/local-state.html#direct-writes
- where did StyledButton component came from?

Esamina le sezioni collegate del tutorial client relative a React Apollo, frammenti, autenticazione, query locali, campi virtuali e scritture dirette. Verifica ogni import mancante elencato, componente, costante, resolver, typeDefs o riferimento a un file sorgente rispetto al contesto del tutorial; il lavoro è completato quando ogni elemento referenziato viene introdotto o ne viene spiegata la posizione.

Scritto dal modello di indicizzazione a partire dal testo della issue.