Add missing info to changes file

changes/bug911_hibernate_precludes_Running

@@ -1,5 +1,6 @@
   o Minor bugfixes:
     - Never vote for a server as "Running" if we have a descriptor for it
       claiming to be hibernating, and that descriptor was published more
-      recently than our last contact with the server.
+      recently than our last contact with the server.  Bugfix on
+      0.2.0.3-alpha; fixes bug 911.