Use the old-style sorts of label strings in the TOC.

Use the old-style sorts of label strings in the TOC.

There are several reasons to do it this way, among which is odd
behavior of the TOC filter if we put anything else there. This also
allows for filtering of the references themsevles in a natural way.

The change, I think, was really an unintended consequence of other
changes connected to showing formatted references in the work area.

(cherry picked from commit 1de4645286e5e51d2e5f6084ee53f3fcb463475d)