restructuring of configuration backends

added propotypes of new control interfaces (xml & dbus)
introduced loadable:
  configuration backends
  control interfaces
using pluggable modules as in EAP

src/charon/sa/ike_sa.c

@@ -746,8 +746,8 @@ static status_t process_message(private_ike_sa_t *this, message_t *message)
 		if (this->ike_cfg == NULL)
 		{
 			job_t *job;
-			this->ike_cfg = charon->cfg_store->get_ike_cfg(charon->cfg_store,
-														   me, other);
+			this->ike_cfg = charon->backends->get_ike_cfg(charon->backends,
+														  me, other);
 			if (this->ike_cfg == NULL)
 			{
 				/* no config found for these hosts, destroy */

src/charon/sa/tasks/ike_auth.c

@@ -511,7 +511,7 @@ static status_t process_r(private_ike_auth_t *this, message_t *message)
 		return NEED_MORE;
 	}
 	
-	config = charon->cfg_store->get_peer_cfg(charon->cfg_store,
+	config = charon->backends->get_peer_cfg(charon->backends,
 									this->ike_sa->get_my_id(this->ike_sa),
 									this->ike_sa->get_other_id(this->ike_sa));
 	if (config)