Remove the undocumented 3rd argument of the emitters (bytes left in buffer).
Add a column to the browser tests that displays JPEGs.
Revise how buffers are allocated.
Progressive jpegs have several very useful advantages over baseline
jpegs:
* Slightly smaller for the same quality (3-7%)
* Load much faster in most browsers.
This adds the `options.progressive` option to the
canvas.jpegCreateStream() function.
Linus Unnebäck
Zach Bjornson
Daniel Beardsley
Tj Holowaychuk
Elijah Hamovitz
Marcello Bastea-Forte