\version "2.19.16"

englishTaglineText = #(format #f
                        "Music typeset using LilyPond ~a~awww.lilypond.org"
                        (lilypond-version)
                        (ly:wide-char->utf-8 #x2014) ;; 2014 = em dash.
                        )
germanTaglineText = #(format #f
                       "Noten gesetzt mit LilyPond ~a ~a www.lilypond.org"
                       (lilypond-version)
                       (ly:wide-char->utf-8 #x2013) ;;2013 = en dash.
                       )

#(define-markup-command
  (format-tagline layout props text)
  (markup?)
  (interpret-markup layout props
    #{
      \markup {
        \italic
        \pad-to-box #'(0 . 0) #'(0 . 3)
        {
          \with-url #"http://lilypond.org/"
          \line $text
        }
      }
    #}
    ))

Tagline = #(define-scheme-function (parser location id) (string?)
             (let
              ((def-tagline
                (lambda (ref)
                  (define tagline (markup #:format-tagline ref)))))
             (cond
              ((eq? id "de") (def-tagline germanTaglineText))
              ((eq? id "en") (def-tagline englishTaglineText)))))