rg3/youtube-dl — pull request #1622 by rbrito (2013-10-18 20:54:29+00:00)
Title: extractor: youtube: Set extension of AAC audio formats to m4a.

This, in particular, eases downloading both audio and videos in DASH formats
before muxing them, which alleviates the problem that I exposed on issue

Furthermore, one may argue that this is, indeed, the case for correctness's
sake.

Signed-off-by: Rogério Brito