Ally Financial (ALLY 0.10%) is a bank. But it isn't your typical bank by any stretch of the imagination, given that it is highly focused on the auto lending space. That focus is increasingly in focus as management executes a business overhaul. This brings up some big news from the fourth-quarter earnings release: the sale of Ally's credit card business.What does Ally Financial do?Ally Financial was created when it was spun off of General Motors. Prior to the 2014 spinoff, it was GM's financing arm. So it sh ...