Fix regression in copyright footer

[dominicus]

Unwanted spacing has appeared with LilyPond 2.18.

Copyright footer compiled with 2.16:

with 2.18:

[glenl]

Ack. This vertical bar replacement scales with font-size but looks reasonable at the default:

      { \with-color #grey
        \center-column {
          \filled-box #'(0 . 0.7) #'(-2 . 1) #0
          }
      }

The PostScript solution produced similar output, was more complex, and also was sensitive to scale.

[PaulMorris]

I encountered a slightly different spacing glitch in pull request #334 :

[dominicus]

@PaulMorris, the published pdf version of your pull-request #334 shows the minor regression as originally identified (i.e. thin whitespace between grey bars).

[PaulMorris]

@dominicus, ok, thanks. (Now I'm wondering why I got something different...?)

[dominicus]

LP's David Kastrup pointed me to a change implemented in 2.18.2 that may be related to this side effect:
http://lists.gnu.org/archive/html/lilypond-user/2014-07/msg00733.html
As a workaround, I found a fontsize for the stacked bar characters that avoids the possible rounding error, now with no visible gap.

[glenl]

I am re-opening this because it has become an issue in 2.19. There has been a change of fonts to TeX Gyre and this font doesn't seem to play well with the stacked bar we are using.

@PaulMorris revisiting this I notice that your image has a different font altogether (compare the "j" in "Project"). According to the pre-2.19 NR, it is possible that this is due to a difference in your Pango installation. I think the intent of the 2.19 change was to fix this sort of thing.