fixed bug with shear, although not sure why way is correct the manual
way I currently have or the fourier way
still need to figure out whats wrong with intensity of fft shear
fixed two bugs. The bigger is I fixed casting of complex numbers to
double. Before I used norm() which is actually the squared magnitude.
Second I fixed fftShear which needed to use negative frequencies rather
than just directly scaling normalized frquencies
finished with fouriershift. Its pretty clear I am going to need to add a
window function though...