New ctrls to retrieve supported signature algorithms and curves and
extensions to s_client and s_server to print out retrieved valued.

Extend CERT structure to cache supported signature algorithm data.
diff --git a/ssl/tls1.h b/ssl/tls1.h
index c5e3a70..cca04b8 100644
--- a/ssl/tls1.h
+++ b/ssl/tls1.h
@@ -252,6 +252,8 @@
 #define TLSEXT_hash_sha256				4
 #define TLSEXT_hash_sha384				5
 #define TLSEXT_hash_sha512				6
+/* Flag set for unrecognised algorithms */
+#define TLSEXT_nid_unknown				0x1000000
 
 /* ExtensionType value from RFC5764 */
 #define TLSEXT_TYPE_use_srtp                           14
@@ -276,6 +278,10 @@
 	const char *label, size_t llen, const unsigned char *p, size_t plen,
 	int use_context);
 
+int SSL_get_sigalgs(SSL *s, int idx,
+			int *psign, int *phash, int *psignandhash,
+			unsigned char *rsig, unsigned char *rhash);
+
 #define SSL_set_tlsext_host_name(s,name) \
 SSL_ctrl(s,SSL_CTRL_SET_TLSEXT_HOSTNAME,TLSEXT_NAMETYPE_host_name,(char *)name)