Comment #4 on issue 2783 by [email protected]: wrong placement of timesignature
http://code.google.com/p/lilypond/issues/detail?id=2783
Revert 0b5d0acd first, because there is no other workaround for this problem. Then maybe add a 'position property for TimeSignature, falling back to the old behavior based on 'line-count. Centering regardless of a staff-line at the center breaks the more common case of a 4-line staff.
