Oct 27 (Reuters) - Overspending on Twitter Inc for $44 billion was the easy part. Now, Tesla Inc (TSLA.O) Chief Executive Elon Musk must prove why he believes that Twitter is worth 10 times that amount and turn around a social media platform that he has spent months ridiculing. Earlier this month, the outspoken billionaire said: "Myself and the other investors are obviously overpaying for Twitter right now. The long term potential for Twitter in my view is an order of magnitude greater than its current value." Musk has provided few concrete details about his plans, and what he has...