Configuration variable for system events

After user acknowledgement a system event is deleted from the event queue.
The configuration variable determines whether it is turned into an appointment
(for later inspection) or not.

Signed-off-by: Lukas Fleischer <lfleischer@calcurse.org>

src/calcurse.c

@@ -707,8 +707,10 @@ int main(int argc, char **argv)
 
 		while (que_ued()) {
 			que_show();
-			que_save();
-			do_storage(0);
+			if (conf.systemevents) {
+				que_save();
+				do_storage(0);
+			}
 			wins_update(FLAG_ALL);
 			que_rem();
 		}