Update release notes (0.28).

Author: awulkiew

Visual_Studio_2017/GraphicalDebugging/release_notes.txt

@@ -1,7 +1,8 @@
 version 0.28
 
 additions:
-- multiple instances of *Watch windows can be opened (up to 10).
+- multiple instances of *Watch windows can be opened (up to 10)
+- try to load as many variables as possible even if exceptions are thrown during loading of some of them
 
 version 0.27