now invoices are by vendor and company

migrator/migrations/1523368332-DOWN-link-invoices-to-vendor.sql

@@ -0,0 +1,5 @@
+-- 1523368332 DOWN link-invoices-to-vendor
+delete from invoices;
+
+alter table invoices drop column vendor_id;
+alter table invoices add column vendor varchar(255);

migrator/migrations/1523368332-UP-link-invoices-to-vendor.sql

@@ -0,0 +1,6 @@
+-- 1523368332 UP link-invoices-to-vendor
+delete from invoices;
+
+alter table invoices drop column vendor;
+alter table invoices add column vendor_id integer;
+alter table invoices add constraint fk_invoices__vendor_id foreign key (vendor_id) references vendors(id);