implement default bridge style

private_includes/base/default_style.ily

@@ -18,6 +18,8 @@ lyricSize = 1.6
 stanzaFormat = "~a."
 refString = "Ref.:"
 refStringWithNumbers = "Ref. ~a:"
+bridgeString = "Bridge:"
+bridgeStringWithNumbers = "Bridge ~a:"
 % hübsche Wiederholungszeichen für den Liedtext
 repStart = "𝄆"
 repStop = "𝄇"