Review request: Preload

Hey Web Platform WG!

The Web Performance Working Group has developed the Preload specification
<https://w3c.github.io/preload/> which provides developers with a
declarative fetch primitive, and enables them to decouple resource loading
from their execution.

The WG invites you to review the latest draft of this specification, which
it believes is ready to transition to Candidate Recommendation:
https://w3c.github.io/preload/

The specification extends the `<link>` attribute with a "preload" `rel`
value as well as the `as` attribute, which indicates the request
destination of the preloaded resource to the browser.

Your feedback on the specification is most welcome! The preferred method
for providing such feedback is by opening an issue on
https://github.com/w3c/preload/issues/

If possible, I'd highly appreciate if you could complete the review before
October 16th, so that we can address any eventual comments and complete the
transition before TPAC.

Thanks! :)
Yoav