Song is a struct


git-svn-id: http://cantata.googlecode.com/svn/trunk@5029 b1e49159-3266-923f-9c3e-04f16369770a
constOnlineDiscId is not used anymore


git-svn-id: http://cantata.googlecode.com/svn/trunk@5030 b1e49159-3266-923f-9c3e-04f16369770a