Hide atrac3+ option if no codec dll/.so installed
Add MpegDemux for demuxing audios.
Fix a tiny bug in Framebuffer.

Prepare for showing video images.
Rewrite and implement MediaEngine.
Rewrite and implement sceMpeg with MediaEngine.
Partly implement scePsmf with MediaEngine.
Hide legacy menu key

http://android-developers.blogspot.com/2012/01/say-goodbye-to-menu-button.html
Merge pull request #2020 from oioitff/mpeg-support

Rewrite some core functions for sceMpeg with ffmpeg.
Merge pull request #2021 from Dzakus/patch-1

Hide legacy menu key
Buildfixes