Shares of Chipotle Mexican Grill, Inc. (NYSE:CMG) are 6.1% higher in premarket action, after the fast-casual chain's board of directors approved a 50-for-1 split -- the company's first stock split ever. In a statement, Chipotle's CFO Jack Hartung said the split will make CMG "more accessible to employees as well a a broader range of investors."Should these premarket gains hold, Chipotle stock will open at around $2,950, surpassing its March 18 record high of$2,813.99. The stock has ripped up the charts ove ...