[FIX] migrate account.invoice class to new API
[FIX] migrate account.invoice class to new API

rvalyi/l10n-brazil,odoo-brazil/l10n-brazil-wip,thinkopensolutions/l10n-brazil,thinkopensolutions/l10n-brazil,odoo-brazil/l10n-brazil-wip,rvalyi/l10n-brazil