MEDIUM: actions: remove ACTION_STOP

Before this patch, two type of custom actions exists: ACT_ACTION_CONT and
ACT_ACTION_STOP. ACT_ACTION_CONT is a non terminal action and ACT_ACTION_STOP is
a terminal action.

Note that ACT_ACTION_STOP is not used in HAProxy.

This patch remove this behavior. Only type type of custom action exists, and it
is called ACT_CUSTOM. Now, the custion action can return a code indicating the
required behavior. ACT_RET_CONT wants that HAProxy continue the current rule
list evaluation, and ACT_RET_STOP wants that HAPRoxy stops the the current rule
list evaluation.
diff --git a/src/stick_table.c b/src/stick_table.c
index 7f3a5a7..a51bde3 100644
--- a/src/stick_table.c
+++ b/src/stick_table.c
@@ -1373,7 +1373,7 @@
 			return ACT_RET_PRS_ERR;
 		}
 	}
-	rule->action = ACT_ACTION_CONT;
+	rule->action = ACT_CUSTOM;
 	rule->action_ptr = action_inc_gpc0;
 	return ACT_RET_PRS_OK;
 }
@@ -1450,7 +1450,7 @@
 	}
 	(*arg)++;
 
-	rule->action = ACT_ACTION_CONT;
+	rule->action = ACT_CUSTOM;
 	rule->action_ptr = action_set_gpt0;
 
 	return ACT_RET_PRS_OK;