Fintech startup Payhawk has raised a $20 million funding round. QED Investors is leading the round with existing investor Earlybird Digital East also participating. Payhawk is building a unified system to manage all the money that is going in and out. Essentially, companies switching to Payhawk can replace several services they already use and that didn’t interact well with each other. Payhawk lets you issue corporate cards for your employees, manage invoices and track payments from a single interface. After signing up, customers get their own banking details with a…