It started with a message sent via LinkedIn in the summer and finished in the late autumn with a strategic partnership and new shareholder for Cali Cali, the healthy snacks firm co-founded by entrepreneurs Tom Gannon and Niall McGrath.   Gannon had sent his message to Boyne Valley Group chief executive Barry Synott only in June, and things moved fast after that. Within three days the three had met, and within three weeks an offer was on the table.   It would take until this month for the deal to be signed, in part due to the slowness of doing business during…