Update apollo client

[HarshRohila]

• removed deprecated apollo-boost and graphql tag, added @apollo/client
• updated example repo (example with code gen repo giving error on npm install, so haven't changed that)
• added @apollo/client@3.0.0 as peer dependency of example repo

other issues

• added empty connected callback in apollo-query(state tunnel - inject props is not working without it)

[jereckley]

Any update on this? I would love to start using some of these 3.0 tools. Anything I can do to help.