Support for fixed DH ciphersuites.

The cipher definitions of these ciphersuites have been around since SSLeay
but were always disabled. Now OpenSSL supports DH certificates they can be
finally enabled.

Various additional changes were needed to make them work properly: many
unused fixed DH sections of code were untested.
diff --git a/CHANGES b/CHANGES
index 0435e29..eeb77b4 100644
--- a/CHANGES
+++ b/CHANGES
@@ -4,6 +4,10 @@
 
  Changes between 1.0.1 and 1.1.0  [xx XXX xxxx]
 
+  *) Support for fixed DH ciphersuites: those requiring DH server
+     certificates.
+     [Steve Henson]
+
   *) Transparently support X9.42 DH parameters when calling
      PEM_read_bio_DHparameters. This means existing applications can handle
      the new parameter format automatically.