Slightly optimize parser

I thought the individual querySelector calls as opposed to
querySelectorAll would have a greater effect, but it's barely noticable.
Well, it's not worse, so I'll leave the uglier code in.
Fix stupid bugs in 'optimized' parser
Further optimize initial page render

Turns out that `onposts` was taking a whole bunch of time just to
iterate through the DSL object, whoops

Also, postinsert fired over and over was too much querying, so
postinsert doesn't run on "boot" anymore, only updates. Still could use
improvment on feature specification to enable more efficient
implementation with the same clean API