Http/2 server push in Rapidweaver

Over 70% of browsers in use already support http/2 allowing web masters to activate server push leading to much faster page loading.

Enabling server push requires changes to the actual website to provide instructions for preloading content. The server then automatically pushes content to the visitor’s cache in advance so any links they click on appear to load in the blink of an eye, since they have effectively loaded already in the background. Users on mobile networks are likely to see a 45% improvement in page loading speed.

In WordPress it looks like this happens automatically but with Rapidweaver we have to get our hands dirty and add instructions manually. Unfortunately there is precious little information available on how this is done and I wondered if anybody has some insight into how this can be achieved in Rapidweaver?