Document WP caching

[oskarrough]

As this project is also to be seen as a guide to combining the Wordpress REST API and Ember I'd like to document how to cache the API.

Let's watch these and document the right approach once it has matured.

• https://github.com/breams/wp-rest-cache
• https://github.com/Automattic/wp-super-cache/pull/121
• https://github.com/WP-API/WP-API/issues/724#issuecomment-242879316

[oskarrough]

Went with https://github.com/airesvsg/wp-rest-api-cache. This seems to work fine and no configuration needed.

https://github.com/oskarrough/ember-wordpress#how-to-enable-caching-for-the-wp-api