Tesla's stock is climbing before the market open Monday as CEO Elon Musk disclosed the purchase of more than 2.5 million shares worth approximately $1 billion. Shares of the electric vehicle maker rose more than 7% in premarket trading. Musk purchased various amounts of shares at different prices on Friday, according to a regulatory filing. The move may be viewed by the markets as the billionaire remaining confident in the company's future. Earlier this month Tesla released a proposed pay package for Mus ...