halide/Halide — pull request #552 by kree-colemcalughlin (2014-11-12 19:00:03+00:00)
Title: Branch visitors for detecting and mutating branches.

This PR replaces #547. The branch has been renamed to correspond to the name of the main file this adds. I have addressed most of the comments that were still open in #547, and made some modifications that are dependent on PR #551.