MercadoLibre has been firing on all cylinders for some time now.Latin American e-commerce leader MercadoLibre (MELI 1.22%) is a riddle. The broader stock market is near all-time highs, but this stock is down roughly 20% from its peak. What gives?There's not an obvious problem with the company. Sometimes, the stock market acts irrationally, and we must take that at face value.However, investors need not sit idly by while such an outstanding growth stock trades at a discount. I had to double-check the fundame ...