Enable compression when sending json to client (#11165)

* Enable compression when sending json to client

Make server compress json content when transmitting to client. Json is quite verbose and compresses well.

A real world example is history_graph requested data for in my case 4 temperature sensors updating every half a second for a graph over 10 days lead to 6MB json which compressed to 200KB using deflate compression.

* Rename variable to request

* Name the variable response instead of request