Customers used to hold up Target as an example of how to run large, yet sparkling stores. Yet in recent years, shopper complaints about sloppier aisles, longer checkout lines, locked-up merchandise and out-of-stock items have dogged the Minneapolis-based retailer, contributing to sagging sales. To help fix that, Target is making a move that may seem counterintuitive: It's shaking up its online strategy. The move is a response to Target's unique strategy of fulfilling the vast majority of its e-