Added music21 and csound examples

examples/music21/create_png.py

@@ -0,0 +1,9 @@
+from music21 import *
+from ziffers import *
+
+# Parse ziiffers object to music21 object
+parsed = zparse('1 2 qr e 124')
+s2 = to_music21(parsed,time="4/4")
+
+# Save object as png file
+s2.write("musicxml.png", fp="examples/music21/output/example.png")