Flip the sign on translations to make them positions.

Also, make renderLayor a public method to clean up tests, and speed up
the swipe animation time from 2s to 1s.  The faster animation makes the
ease out way less “slow.”
Add and clean unit tests
Eat Lint Blintz
Re-privatize renderLayout
Oh, right, there's more to the world than unit tests.
I could not see the added value of having two tests
Merge pull request #82 from WebFilings/render_placeholders_on_flick

Make placeholders show during fast swipe/flick