Gregorian ictuses.

[Mirosław Doroszewski]

Placing ictuses too low and mostly (or only) below a staff.
Solution with "\override Script #'padding = #-0.1" is not complete: works  
only vertically and for neumes placed between staff lines.

Example file:

\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\

\version "2.10.0"
\include "gregorian-init.ly"
\paper {
        #(set-paper-size "a4")
        #(layout-set-staff-size (* 18.0 pt))
        %left-margin = 7 \mm
        %line-width = 88 \mm
        indent = 0 \mm
        %ragged-right = ##t
        %ragged-bottom = ##f
        %ragged-last-bottom = ##f
        between-system-space = #(* 0.1 mm)
        between-system-padding = #(* 0.1 mm)
}

\score {
        \new VaticanaStaff {
                \context VaticanaVoice = "cantus" {
                        \set VaticanaStaff.createSpacing = ##f
                        \override VaticanaStaff.StaffSymbol #'color = #red
                        \override VaticanaStaff.LedgerLineSpanner #'color = #red
                        \override Score.BarNumber #'transparent = ##t
                        \override Score.Clef #'extra-offset = #'(-0.75 . 0.0)
                        \override Script #'padding = #-0.1
                        \clef "vaticana-do1"
                        \relative {
                                \[ a \ictus \]
                                \[ d \ictus \]
                                \[ g \ictus \]
                                \finalis
                        }
                }
        }
}