Add DTLS support.

ssl/ssl_err.c

@@ -456,6 +456,8 @@ static ERR_STRING_DATA SSL_str_reasons[]=
 {ERR_REASON(SSL_R_WRONG_VERSION_NUMBER)  ,"wrong version number"},
 {ERR_REASON(SSL_R_X509_LIB)              ,"x509 lib"},
 {ERR_REASON(SSL_R_X509_VERIFICATION_SETUP_PROBLEMS),"x509 verification setup problems"},
+{ERR_REASON(SSL_R_READ_TIMEOUT_EXPIRED)  ,"read timeout expired"},
+{ERR_REASON(SSL_R_COOKIE_MISMATCH)       ,"cookie mismatch"},
 {0,NULL}
 	};