Yes, exactly. I have a book there, it is still hosted on RStudio Connect (which underlies bookdown.org as I believe).
To use Continuous Integration with Travis-CI I would rather host it on Netlify (because I think, it may be difficult to upload to to RStudio Connect via Travis, not sure how to make the credentials available atm).
My current idea would be to, redirect the link on bookdown.org to a netlify website. I think many books, listed on the first page do may sth like this, as they link to an external url.
(Hope it is clearer now, it's kind more than one question I guess,)