tests: fix compilation of tests on FreeBSD 11

Some includes were missing in .h files, and the tests must be linked
with intl and execinfo on FreeBSD.

src/plugins/relay/relay-client.h

@@ -20,6 +20,8 @@
 #ifndef WEECHAT_RELAY_CLIENT_H
 #define WEECHAT_RELAY_CLIENT_H 1
 
+#include <time.h>
+
 #ifdef HAVE_GNUTLS
 #include <gnutls/gnutls.h>
 #endif /* HAVE_GNUTLS */

src/plugins/relay/relay-raw.h

@@ -20,6 +20,8 @@
 #ifndef WEECHAT_RELAY_RAW_H
 #define WEECHAT_RELAY_RAW_H 1
 
+#include <time.h>
+
 #include "relay-client.h"
 
 #define RELAY_RAW_BUFFER_NAME     "relay_raw"

src/plugins/relay/relay-server.h

@@ -20,6 +20,8 @@
 #ifndef WEECHAT_RELAY_SERVER_H
 #define WEECHAT_RELAY_SERVER_H 1
 
+#include <time.h>
+
 #ifdef HAVE_GNUTLS
 #define RELAY_SERVER_GNUTLS_DH_BITS 1024
 #endif /* HAVE_GNUTLS */

src/plugins/relay/weechat/relay-weechat-msg.h

@@ -20,6 +20,8 @@
 #ifndef WEECHAT_RELAY_WEECHAT_MSG_H
 #define WEECHAT_RELAY_WEECHAT_MSG_H 1
 
+#include <time.h>
+
 struct t_relay_weechat_nicklist;
 
 #define RELAY_WEECHAT_MSG_INITIAL_ALLOC 4096