[ADD] inter_company_rules module

- Internal Task https://www.odoo.com/web#id=6962&view_type=form&model=project.task&action=333&active_id=131
- Pad https://pad.odoo.com/p/r.IOcwt0uWZx1OKJiT
can you rename with "create_intercompany_invoice"? and this method should be @api.multi.