Draw the pokey using HTML and CSS

* Replace the pokey PNG with a rotated div with a box shadow, which can
  be scaled (or transformed arbitrarily) smoothly
* Move the guider 10px closer to its target
* Add the uprightdownleft tour, which demonstrates the pokey in all four
  directions

Change-Id: Id1b837f3a0f983b89935f0003367705a92d10cee