Bug 10046: Standardize terms used in invoices

Bug 10046: Standardize terms used in invoices

Changes are:
budget > where actually fund is meant
branch > library
bookseller, supplier > vendor

To test:

1) Receive a shipment, check the little form where you
   enter your invoice number for correct use of terms.
2) Receive some orders and save finish receiving.
3) Search for your created invoice. Check filters and
   results table for correct use of terms.
4) Look at the details of your invoice, repeat check there.

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Jared Camins-Esakov <jcamins@cpbibliography.com>