Add routraverse logic

We are now theoretically code-complete
Allow nameless globbing
fixes round 1: FOREACH DOES NOT WORK THAT WAY
fixes round 2: fs.exists has no error param

On one hand this would have been obvious if I'd bothered to read the docs more closely. On the other hand, what why
fixes round 3: glob derp, params derp
fixes round 4: mep mep mep is actually a big deal

if I'm going to avoid this in callbacks, I need to actually avoid this in callbacks
Render content on post discovery

You want content stored with the post, for one thing, for page
listings (where it shows multiple posts). Not to mention you've
got cached renders this way.