ChordEvents represent Chords in the Song Parameters. These map onto the Event
structure.
struct ChordEvent {
struct ChordEvent *next; /* The next event in the list. */
long time; /* When this event occurs. */
char type; /* What type of event. */
unsigned char root; /* Root note. */
char flats; /* Chord root is a flat. */
char pad;
unsigned long chordid; /* Chord id. */
struct Chord *chord; /* Chord. */
};