* lily/vaticana-ligature-engraver.cc (need_extra_space): renamed
to need_extra_horizontal_space; bugfix: use class scope to avoid
global namespace pollution
* Documentation/user/instrument-notation.itely (ligatures): added
comment on possible future syntax change and how to work around
* lily/vaticana-ligature-engraver.cc, mf/parmesan-heads.mf
(epiphonus, cephalicus): fine-tune shape of plica head for narrow
intervals (fixes agnus dei example)
* lily/include/mensural-ligature.hh: make comments clearer
* lily/mensural-ligature.cc: line thickness of flexa shape
(originally by Pal Benko; slightly modified)
* Documentation/user/instrument-notation.itely (white mensural
ligatures): selected a more illustrative example