fix english quotes

songs/the_kingston_trio/greenback_dollar.sg

@@ -34,10 +34,10 @@
   \begin{repeatedchords}
     \begin{verse}
       \[Em]When I was a little \[G]baby
-      My \[Em]Mama said: {\og}Hey \[G]Son
+      My \[Em]Mama said, ``Hey \[G]Son
       \[Gm]Travel where you will and grow to be a man
       And \[D]sing what must be \[Em]sung, oh boy
-      \[D]Sing what must be \[Em]sung{\fg}
+      \[D]Sing what must be \[Em]sung''
     \end{verse}
 
     \begin{verse}