Function normalize

examples/computer_vision/matching.cpp:17–21

using namespace af;

array normalize(array a) {
    float mx = af::max<float>(a);
    float mn = af::min<float>(a);
    return (a - mn) / (mx - mn);
}

void drawRectangle(array& out, unsigned x, unsigned y, unsigned dim0,
                   unsigned dim1) {