[opus] Opus now supported at Magnatune

[John Buckman]

> If you pass --genre multiple times, it will actually encode multiple GENRE tags in the file. Not sure how many players will properly handle such a thing, though (my prediction: not many, though I think VLC will concatenate them into a comma-separated list).

My mistake, I didn't read the man page carefully enough, which does state this:
> Set the genre comment field to genre. This option may be specified multiple times to tag a track with multiple overlapping genres.

> "Paper Lights" from <http://magnatune.com/artists/albums/ehren-lines/> has been prominently featured at <http://www.opus-codec.org/examples/> and articles like <https://hacks.mozilla.org/2012/07/firefox-beta-15-supports-the-new-opus-audio-format/>,

Great!

> etc. Sadly, when I "Click to play a song" on the Magnatune page, though, it tries to use Flash (which I don't have installed).

Apologies for this -- I'm using the soundmanager2 javascript library, and am tied to its behavior.  

I believe that if flash is not installed, it is supposed to use javascript-based playback, so something is odd. However, flash blockers cause problems, as well as older browsers that don't have html-based audio playback features.

If you follow up with me via personal email, I'll be happy to try to debug the situation with you.  

I wasn't sure what bit rate was appropriate for "Very high quality" with opus, i.e. something that was "commonly indistinguishable from a WAV file". Any advice on that is appreciated.

-john