By Sheila Dang and Greg Roumeliotis (Reuters) – Elon Musk became Twitter Inc’s owner on Thursday, firing top executives and providing little clarity over how he will achieve the lofty ambitions he has outlined for the influential social media platform. “The bird is freed,” he tweeted, referencing Twitter’s bird logo in an apparent nod to his desire to see the company have fewer limits on content that can be posted. The CEO of electric car maker Tesla Inc has, however, also said he wants to prevent the platform from becoming an echo chamber for hate and division. Other goals include wanting to …