fill in a few more blanks in the changes files

changes/bug17592

@@ -3,7 +3,7 @@
      CircuitIdleTimeout and PredictedPortsRelevanceTime into a single option
      called CircuitsAvailableTimeout. Also, allow the consensus to control
      the default values for both this preference, as well as the lifespan
-     of relay-to-relay connections. Fixes bug 17592.
+     of relay-to-relay connections. Fixes bug 17592; bugfix on 0.2.5.5-alpha.
    - Increase the intial circuit build timeout testing frequency, to help
      ensure that ReducedConnectionPadding clients finish learning a timeout
      before their orconn would expire. The initial testing rate was set back

changes/bug17604

@@ -6,7 +6,8 @@
      status early. Also, additionally alter the connection selection
      logic to prefer the oldest valid connection for extend cells.
      These two changes should reduce the number of long-term connections
-     that are kept open between relays. Fixes bug 17604.
+     that are kept open between relays. Fixes bug 17604; bugfix on
+     0.2.5.5-alpha.
    - Relays will now log hourly statistics on the total number of
      connections to other relays. If the number of connections per relay
      unexpectedly large, this log message is at notice level. Otherwise

changes/bug21654

@@ -1,4 +1,4 @@
   o Minor bugfixes (testing):
     - Use unbuffered I/O for utility functions around the process_handle_t
       type. This fixes unit test failures reported on OpenBSD and FreeBSD.
-      Fixes bug 21654.
+      Fixes bug 21654; bugfix on 0.2.3.1-alpha.