PayPal just had a phenomenal quarter, yet the stock hasn't budged.PayPal (PYPL -2.36%) has been a turnaround investment opportunity for some time, but the reversal is taking longer than many would like. Still, that doesn't discount how great of an investment PayPal could be once the rest of the market finally gets on the same page.PayPal gained momentum in the first quarter, and I wouldn't be surprised if it's in the beginning stages of a rally, making the stock a no-brainer buy.PayPal's Q1 was a great sign ...