Add print CSS via "@media only print"

No separate css file for print only since that downgrades performance on many clients, see http://www.phpied.com/5-years-later-print-css-still-sucks/
Merge branch 'master' of github.com:accu-rate/website
Add meta: pagetitle to application page
Rename page to reflect page title (SEO) and fix link (leave out .md ending)