insertbefore <body>

YouTube has this lovely habit of changing their element IDs every 2 months. This
is breaking the bookmarklet every time. Screw them, we will just inject the
HTML above the <body>

Random Office quote
Dwight: Pull over at exit 40. There is a Liz Claiborne outlet. I know you like
        that store. Go inside and shop, until I can meet you.
Jan:    How do you know I like that store?
Dwight: Many of your blouses are Claiborne's.
Jan:    How do you know that?
Dwight: Part of my job.
Jan:    No it's not. It's officially not.
Dwight: ...noted.