Prevent Fraction type to get saved to json for standard durations

engine/items.py

@@ -366,6 +366,9 @@ class Duration(object):
                 else: #the highest value in datalist was smaller
                     return None
 
+        if completeDuration == int(completeDuration):
+            completeDuration = int(completeDuration)
+
         durList = [D1024, D512, D256, D128, D64, D32, D16, D8, D4, D2, D1, DB, DL, DM]
         guessedBase = _closest(completeDuration, durList)        
 
@@ -1341,8 +1344,10 @@ class Chord(Item):
         for note in self.notelist:
             oldValues.append(note.duration.copy()) #we don't actually need a copy since we create a new one. But better safe than sorry. This matches also the behaviour of the other duration change functions.
             complDur =  note.duration.completeDuration()
-            #newTicks = complDur / newparts
+            
+            #newTicks = complDur / newparts                        
             note.duration = Duration.createByGuessing(Fraction(complDur, newparts))
+            
 
         #Now we have one note with the duration the user wants to have. Make n-1 copies-
         spawnedNotes = []