Configure, internal FFmpeg: Enable asf muxer and wmav2 encoder for ripping CDs to wma2.
CDRip: Add definitions for ripping audio CDs to AAC and WMA with FFmpeg.

More formats can easily be added but I think we should be parcimonious: If we add too much of them the users will likely be lost.

So far, AAC seems interesting for iTunes users (iOS, OSX, etc.) and WMA for windows users.
Allow selecting AAC and WMA audio CD ripping for the GUI.

This commit should likely be ammended with translation support added.