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/apps/s_server.c b/apps/s_server.c
index 1f4b85b..4603cda 100644
--- a/apps/s_server.c
+++ b/apps/s_server.c
@@ -2472,7 +2472,10 @@
 	if (SSL_get_shared_ciphers(con,buf,sizeof buf) != NULL)
 		BIO_printf(bio_s_out,"Shared ciphers:%s\n",buf);
 	str=SSL_CIPHER_get_name(SSL_get_current_cipher(con));
+	ssl_print_sigalgs(bio_s_out, con);
+	ssl_print_curves(bio_s_out, con);
 	BIO_printf(bio_s_out,"CIPHER is %s\n",(str != NULL)?str:"(NONE)");
+
 #if !defined(OPENSSL_NO_TLSEXT) && !defined(OPENSSL_NO_NEXTPROTONEG)
 	SSL_get0_next_proto_negotiated(con, &next_proto_neg, &next_proto_neg_len);
 	if (next_proto_neg)
@@ -2806,6 +2809,8 @@
 					}
 				BIO_puts(io,"\n");
 				}
+			ssl_print_sigalgs(io, con);
+			ssl_print_curves(io, con);
 			BIO_printf(io,(SSL_cache_hit(con)
 				?"---\nReused, "
 				:"---\nNew, "));