scrolling of long song formats

[nilsbecker]

it would be nice to be able to see the full formatted song name in the statusline, by auto-scrolling sideways. now it seems the only way to see long names is using a format that skips stuff in the middle, or using 'e' to get detailed song info, yes?

[boysetsfrog]

Scrolling of the current song (in the statusline) is now supported as d191936, but I also want to add the option to scroll sideways the title of the selected song.