mp4v2 is used by easy-tag and cmus, but those require different
versions that are not API compatible.
Add a devel block for r479.
Add patches for stable committed in r472 inline. Patches fix
compile errors with clang, but are not available via direct url.
Stable works with easy-tag and can open .m4a files from iTunes.
Devel works with cmus and can play .m4a files from iTunes.
Compiles with all 5 compilers from XCode-4.3.2, 4.0.2 on Lion
and Snow Leopard. Main discussion was in Homebrew/homebrew#7998ClosesHomebrew/homebrew#11275.
Signed-off-by: Jack Nagel <jacknagel@gmail.com>
