Add links to the remaining HTML files in the README

I very much like these examples, but the HTML results are not all accessible in the the README. Could you add the rest?

I tried to access the one on measurement error, but I could only get the HTML to display in github as the HTML text, not as it would be readable in a browser.

I could, of course, download the `.Rmd` file and compile it, but it would be handier if I didn't have to.