TT#157700 invoice template call directions

Change-Id: I3fb18a7118161df6e782d53e5d47a3f84a00b16d

db_scripts/diff/15717.down

@@ -0,0 +1,3 @@
+USE billing;
+
+ALTER TABLE invoice_templates DROP COLUMN call_direction;

db_scripts/diff/15717.up

@@ -0,0 +1,3 @@
+USE billing;
+
+ALTER TABLE invoice_templates ADD COLUMN call_direction enum('in','out','in_out') NOT NULL DEFAULT 'out';