A staff member prepares a drone for the delivery at the drone delivery service base run by Zipline in Omenako, Ghana.Photographer: Ruth McDowall/AFP/Getty ImagesZipline, a drone delivery and logistics startup, has raised more than $600 million in new funding, boosting its valuation to $7.6 billion, as it expands commercial deployments.The firm’s fundraising round included backing from Valor Equity Partners and participation from investors such as Tiger Global, Fidelity Management and Research Co...