Merge branch 'master' of ssh://jomand@git.sv.gnu.org/srv/git/lilypond

Merge branch 'master' of ssh://jomand@git.sv.gnu.org/srv/git/lilypond

* 'master' of ssh://jomand@git.sv.gnu.org/srv/git/lilypond:
  Add link.
  Revert "seventh patch from Joe: add regression test for mixed clefs and octavations"
  Revert "sixth patch from Joe: fix displayLilyMusic for clefs"
  Revert "fourth patch from Joe: revert revert fix line ideal distance to favour mo"
  Revert "second patch from Joe: fix a silly mistake with infinite stiff springs"
  Revert "fix input regression cluster cross-staff.ly"
  Revert "third patch from Joe: avoid NaN with springs of zero length"
  Revert "first patch from Joe: fix a bug FIXME number"
  seventh patch from Joe: add regression test for mixed clefs and octavations
  sixth patch from Joe: fix displayLilyMusic for clefs
  fix input regression cluster cross-staff.ly
  fourth patch from Joe: revert revert fix line ideal distance to favour mo
  third patch from Joe: avoid NaN with springs of zero length
  second patch from Joe: fix a silly mistake with infinite stiff springs
  first patch from Joe: fix a bug FIXME number
  Fix underline markup x extent