mozjpeg 1.0.1 (new formula)

Add mozjpeg, a JPEG encoder created by Mozilla that focuses on efficient encoding.

[More information is available here](https://blog.mozilla.org/research/2014/03/05/introducing-the-mozjpeg-project/).
I copied the test from jpeg-turbo, but used ```-optimize``` instead of ```-perfect``` since I believe ```-perfect``` can fail based on the characteristics of the image, rather than a problem with the compilation. It works presently, but I think this is safer in case ```DefaultDesktop.jpg``` changes in the future. ```-optimize``` is a more common feature anyways.

So is that satisfactory?