Lyrics-avoiding barlines are too long

[Zoltan Selyem]

> I'm not top posting.

%% "Making lyrics avoid barlines" used with StaffGroup
%% causes barlines to extend under the last staff
%% and causes repeat signs not to be continuous.

\version "2.10.15"
\paper{ ragged-right=##t }
\context StaffGroup
<<
  \relative c' { c1 d \bar ":|" }
  \addlyrics { c d }
  \relative e' { e1 f }
  \addlyrics { e f }
>>
\layout{
  \context {
    \Lyrics
      \consists "Bar_engraver"
      \consists "Separating_line_group_engraver"
      \override BarLine #'transparent = ##t
  }
}