Midi sustain working when envelope is on (#3730)

* midi sustain working when envelope is on

* pressing sustain pedal again doesn't pause release

include/NotePlayHandle.h

@@ -156,6 +156,11 @@ public:
 		return m_released;
 	}
 
+	bool isReleaseStarted() const
+	{
+		return m_releaseStarted;
+	}
+
 	/*! Returns total numbers of frames played so far */
 	f_cnt_t totalFramesPlayed() const
 	{
@@ -297,6 +302,7 @@ private:
 											// release of note
 	NotePlayHandleList m_subNotes;			// used for chords and arpeggios
 	volatile bool m_released;				// indicates whether note is released
+	bool m_releaseStarted;
 	bool m_hasParent;						// indicates whether note has parent
 	NotePlayHandle * m_parent;			// parent note
 	bool m_hadChildren;