Prepare fields in dtabase to store if time spent was invoiced or not.

htdocs/install/mysql/migration/3.8.0-3.9.0.sql

@@ -105,3 +105,8 @@ ALTER TABLE llx_product ADD COLUMN onportal tinyint DEFAULT 0 after tobuy;
 
 ALTER TABLE llx_user ADD COLUMN employee tinyint DEFAULT 1;
 
+
+ALTER TABLE llx_projet_task_time ADD COLUMN invoice_id integer DEFAULT NULL;
+ALTER TABLE llx_projet_task_time ADD COLUMN invoice_line_id integer DEFAULT NULL;
+
+

htdocs/install/mysql/tables/llx_projet_task_time.sql

@@ -26,5 +26,7 @@ create table llx_projet_task_time
   task_duration    double,
   fk_user          integer,
   thm			   double(24,8),
+  invoice_id       integer DEFAULT NULL,				-- If we need to invoice each line of timespent, we can save invoice id here
+  invoice_line_id  integer DEFAULT NULL,                -- If we need to invoice each line of timespent, we can save invoice line id here
   note             text
 )ENGINE=innodb;