Add changes entry for upcasting of shared_ptr's

Author: wsfulton

CHANGES.current

@@ -7,6 +7,9 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.0.2 (in progress)
 ===========================
 
+2020-01-24: etse-dignitas, wsfulton
+            #1533 [C#, D, Java] Fix upcasting for shared_ptr's of templated types.
+
 2020-01-16: mcfarljm
             #1643 #1654 When using -doxygen, fix segfault when nameless parameters or vararg parameters
             are used.