moved force_encap to ike_config, enables responder to enforce udp encapsulation

fixed bugs in force_encap code

src/starter/starterstroke.c

@@ -228,6 +228,7 @@ int starter_stroke_add_conn(starter_conn_t *conn)
 		msg.add_conn.rekey.fuzz = conn->sa_rekey_fuzz;
 	}
 	msg.add_conn.mobike = conn->policy & POLICY_MOBIKE;
+	msg.add_conn.force_encap = conn->policy & POLICY_FORCE_ENCAP;
 	msg.add_conn.algorithms.ike = push_string(&msg, conn->ike);
 	msg.add_conn.algorithms.esp = push_string(&msg, conn->esp);
 	msg.add_conn.dpd.delay = conn->dpd_delay;