exports: add unexported classes from Common/DataObjects to exported index (#926)

fix #926

src/Common/index.ts

@@ -1,4 +1,3 @@
-export * from "./DataObjects/Fraction";
-export * from "./DataObjects/Pitch";
+export * from "./DataObjects";
 export * from "./Enums";
 export * from "./FileIO";

src/MusicalScore/Graphical/MusicSheetCalculator.ts

@@ -266,7 +266,7 @@ export abstract class MusicSheetCalculator {
         // delete graphicalObjects (currently: ties) that will be recalculated, newly create GraphicalObjects streching over a single StaffEntry
         this.clearRecreatedObjects();
 
-        //this.graphicalMusicSheet.initializeActiveClefs(); // could have been changed since last render?
+        // this.graphicalMusicSheet.initializeActiveClefs(); // could have been changed since last render?
 
         this.createGraphicalTies();