SYDNEY, Aug 2 (Reuters) - Two Indian navy ships docked in Papua New Guinea on Wednesday, underscoring the strategic importance of the country to global superpowers the United States and China and their allies. The INS Kolkata guided missile destroyer and INS Sahyadri frigate will stay in PNG's capital Port Moresby for two days, an Indian embassy official said. The visit will "enhance maritime cooperation and security in the region", an embassy statement added. India currently holds the rotating presidency of the G20. The ships will then join naval exercises in Australia as part of the Quadrilateral Security Dialogue, or...