Fixes bug with transparency 

This bug appeared when we moved from the old version of THREE.js to the new version that we have.

Basically, the problem is that whenever you had two elements that are transparent in the same location (like in a jackknifed plot), one or the other would be rendered first and if the ellipse was rendered first, then the sphere would not seem to be there.

All the examples were updated with the latest `emperor.js`.