Turn on in-memory response caching

v1.4

Example how to turn on application level cache (in-memory) (#9)

Add cache hints

Cache hints (#8)

* Set max age to 60 sec if you fetch category with its products

Turn on persisted queries

Use persisted queries (#7)

* use persisted queries

* Add feature toggles for persistent queries.
Add global cache-control value

* Turn on persisted queries

Introduce dataloaders

Use dataloaders (#6)

* use dataloaders

Basic client & server applications

v1.0

Remove npm scripts that are not working / not used, update readme (#10)