Stopwatch: Wait for the Spice to load before displaying things.

This makes sure the divs display at the right time so the layout doesn't break. It's very similar to the one in timer.js

![screen shot 2014-08-07 at 1 08 57 pm](https://cloud.githubusercontent.com/assets/81969/3848516/dd78c8ee-1e70-11e4-8ff2-721f6360358c.png)

It also fixes https://github.com/duckduckgo/zeroclickinfo-spice/issues/940.
Good catch!