Merging upstream version 2.5.2.

Signed-off-by: Daniel Baumann <daniel@debian.org>

CHANGES

@@ -1,3 +1,45 @@
+2020-03-25 Jerry Lundström
+
+    Release 2.5.2
+
+    This release tweaks the reconnect code for TCP and DoT.
+
+    For TCP, atomic operations are used to signal the need to reconnect
+    from the receiving thread to the sending, as the sending is the one in
+    charge of reconnecting.
+    This speeds up detection of connection lost which reduces the amount of
+    lost queries on a disconnect.
+
+    This change does not affect DoT as much, as the SSL context shared
+    between the threads are protected by a mutex.
+    But a bug was found in `sendto()` for DoT that could drop a query if
+    the socket was busy sending.
+
+    The connect and reconnect socket events has been split into connecting,
+    connected and reconnecting, reconnected. This is to report more correct
+    reconnect events when it comes to DoT, because the connection can be
+    lost while negotiating TLS.
+
+    Lastly, additional tests has been added for the network code.
+
+    d9e5663 net test
+    22f49df network tests
+    8e5b56e reconnect
+
+2020-03-22 Jerry Lundström
+
+    Release 2.5.1
+
+    This release re-adds support for TYPEnnn and ANY in the datafile, this
+    was missed during the removal of the dependency on BINDs development
+    libraries in v2.4.0.
+
+    Also note that with v2.5.0, this software now depends on Concurrency
+    Kit (ck) for atomic operations.
+
+    924e6ea ANY
+    0a444c0 TYPEnnn
+
 2021-03-12 Jerry Lundström
 
     Release 2.5.0