Add tests that fail to check the copy of supplier_invoice_number to
reference on create and write
Make the failing test passes, the fields is named supplier_invoice_number

not supplier_invoice_reference

Conflicts:
	account_invoice_reference/account_invoice.py

Wrong cherry-pick
ids could be int/long
Merge pull request #53 from guewen/account_invoice_reference-ref-fix

Wrong field name