follow XDG for default download directory

closes #413

src/common/cfgfiles.c

@@ -754,7 +754,7 @@ load_config (void)
 		snprintf (prefs.hex_dcc_dir, sizeof (prefs.hex_dcc_dir), "%s\\Downloads", out);
 	}
 #else
-	snprintf (prefs.hex_dcc_dir, sizeof (prefs.hex_dcc_dir), "%s/downloads", get_xdir ());
+	strcpy (prefs.hex_dcc_dir, g_get_user_special_dir(G_USER_DIRECTORY_DOWNLOAD));
 #endif
 	strcpy (prefs.hex_dnsprogram, "host");
 	strcpy (prefs.hex_gui_ulist_doubleclick, "QUERY %s");