Fix bug : prevent identical tags on operation

include/sql/patch/upgrade181.sql

@@ -0,0 +1,11 @@
+begin;
+
+
+-- create constraint
+alter table operation_tag add constraint tag_operation_uq unique (jrn_id,tag_id);
+
+-- remove duplicate
+delete from operation_tag where opt_id in (select a.opt_id from operation_tag a join operation_tag b on (a.jrn_id=b.jrn_id and a.tag_id=b.tag_id) where a.opt_id  < b.opt_id );
+
+insert into version (val,v_description) values (182,'Prevent to add several time same tag on an operation');
+commit;