SYDNEY (Reuters) – Australias largest telecommunications company Telstra Ltd said on Tuesday it had paid $270 million to buy out Silicon Valley-based video platform company Ooyala as part of a deeper push into digital media. Telstra already owned 23 percent of Ooyala after investing $61 million over the past two years and will take its stake to 98 percent under the deal, assuming it is approved by U.S. regulators. …