Added a comment to the Linearity namespace describing the linearity code.
Added a comment to the Linearity namespace describing the linearity code.


Former-commit-id: a11da0efcc8cef5aba2594b4a6a6a044bda4fadf
darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide