PayPal's stock is just getting started.These past few weeks have been a welcome change if you're a PayPal (PYPL -0.04%) investor. Instead of the stock moving sideways after its dramatic decline, it finally showed some life and rallied as much as 20%. The stock still has a long way to go -- it's still down 75% from its all-time highs. However, the recent rebound could be the beginning of a much larger move, and investors who missed out on the first part of the rally have the opportunity to participate in a m ...