Formats JS code as commented that is not commented

[stevecj]

In the first block of code in the http://techblog.stevej.name/2016/04/09/making-music-with-the-webaudio-api-part-3/ post, a large section of the JavaScript code is formatted as comment, but it is not commented.

Apparently, everything after the slash in 1/12 on the line that reads , frequencyHz = 440 * Math.pow(2, noteNum * 1/12) is being incorrectly identified.