Add Midi Reversing (#7606)

Adds the ability to reverse the selected midi notes in the PianoRoll.

The tool is located under the wrench icon in the PianoRoll and can also be triggered with Shift-R.

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Co-authored-by: szeli1 <143485814+szeli1@users.noreply.github.com>

include/MidiClip.h

@@ -79,6 +79,9 @@ public:
 	Note * addStepNote( int step );
 	void setStep( int step, bool enabled );
 
+	//! Horizontally flip the positions of the given notes.
+	void reverseNotes(const NoteVector& notes);
+
 	// Split the list of notes on the given position
 	void splitNotes(const NoteVector& notes, TimePos pos);
 

include/PianoRoll.h

@@ -248,6 +248,7 @@ protected slots:
 	void clearGhostClip();
 	void glueNotes();
 	void fitNoteLengths(bool fill);
+	void reverseNotes();
 	void constrainNoteLengths(bool constrainMax);
 
 	void changeSnapMode();