Use HTTPS everywhere

Was seeing a few mixed content errors while navigating around the site. Hopefully this will fix that.

Also of note: going to [http://cryptic.io](http://cryptic.io) will redirect you to [https://cryptic.io](https://cryptic.io), but only on the homepage. Might be worth turning on the CloudFlare Page Rule "Always use HTTPS" so all other pages redirect to https. @MarcoPolo, @mediocregopher, or @kinghrothgar should be able to enable that.