Regtest - difference from 13.30 to 13.31

[Phil Holmes]

I'll be posting a few issues here over the next day or two, but a major 
difference between 2.13.30 and .31 is shown with 
page-spacing-tall-headfoot.ly.

In .30 it fits the music neatly onto 2 pages, with 2 systems on page 1 and 8 
systems on page 2.  In .31 it uses 4 pages, with 2 systems on page 1, 3 
spaced-out systems on page 2, 2 systems on page 3 and 2 ragged-bottom 
systems on page 4.  I would have posted this as a bug immediately, but 
comparison with 2.12.3 shows that 4 pages are used there as well.  In that 
version, the systems per page are 1, 6, 1, 2 respectively.  Almost certain 
this is a bug, but would welcome thoughts from the developers.

--
Phil Holmes
Bug Squad