add namednote documentation (#19)

Nero Blackstone​ · web-flow · commit 58ae443133ad · 2023-06-08T16:53:41.000+01:00
diff --git a/docs/src/midi/notes.md b/docs/src/midi/notes.md
@@ -73,3 +73,11 @@ note_to_fundamental
 hz_to_pitch
 pitch_to_hz
 ```
+## NamedNote
+
+Note with specific note name. This type need `MusicManipulations.jl`.
+
+```@docs
+NamedNote
+NamedNotes
+```
