Headers request - Add Cache-Control headers to responses
Hi @jakewmeyer 

I've noticed no `Cache-Control` headers have been added to the API responses. Since applications might want to optimise their caching providing the `Cache-Control` headers could be very useful. Would it be possible to add these? I am for example using Retrofit to make API calls. If `Cache-Control` is added I can less frequent make calls to the API.

Cheers!
Jeroen