Waterloo-based Open Text Corp is acquiring the customer communications management assets of HP Inc for US $315 million and the two firms will explore future opportunities to work together. The deal marks the second acquisition Open Text has made from HP, following its purchase of HPs content management software tools for $170 million. Open Text is a world-leading provider of enterprise information management software and the latest HP acquisition will add at least $110 million in annual revenues. Its 2015 revenue was $1.9 billion….