Update changelog

Author: linev

changes.md

@@ -6,7 +6,8 @@
 3. Fix - correctly display ^2 and ^3 in SVG text output 
 4. Fix - do not show tooltips for empty TProfile bins
 5. Fix - statbox toggling was not working on subpads
-6. Fix - positioning of 3D objects in Chrome in complex layouts 
+6. Fix - positioning of 3D objects in Chrome in complex layouts
+7. Fix - difference in TF1 between ROOT5/6 (#54)  
 
 
 ## Changes in 4.5.0