Changes between 1.0.1 and 1.1.0 [xx XXX xxxx]
+ *) New ctrls to retrieve and set certificate types in a certificate
+ request message. Print out received values in s_client. If certificate
+ types is not set with custom values set sensible values based on
+ supported signature algorithms.
+ [Steve Henson]
+
+ *) Support for distinct client and server supported signature algorithms.
+ [Steve Henson]
+
+ *) Add certificate callback. If set this is called whenever a certificate
+ is required by client or server. An application can decide which
+ certificate chain to present based on arbitrary criteria: for example
+ supported signature algorithms. Add very simple example to s_server.
+ This fixes many of the problems and restrictions of the existing client
+ certificate callback: for example you can now clear an existing
+ certificate and specify the whole chain.
+ [Steve Henson]
+
*) Add new "valid_flags" field to CERT_PKEY structure which determines what
the certificate can be used for (if anything). Set valid_flags field
in new tls1_check_chain function. Simplify ssl_set_cert_masks which used