Start breaking up music into pieces/score parts

src/scores/sax-tenor-solo/song-of-the-volga-boatmen.ly

@@ -0,0 +1,12 @@
+\include "song-of-the-volga-boatmen.ly"
+
+\book {
+    \score {
+        \new Staff \with {
+            instrumentName = "Tenor Sax"
+        } {
+            \transpose g' bf'
+            \melody
+        }
+    }
+}