#214 Fourier Space Image Manipulation

[Katherine Ann Scott]

Add basic support to the image class for Fourier transforms and filtering. Add three methods for automatically low pass, high pass, and band pass filtering.

fftimg = img.FFT()
new_img = img.IFT()
img.lowPassFilter(cutoff=10)
img.highPassFilter(cutoff=100)
img.bandPassFilter(low=10,high=100)

see: http://opencv.willowgarage.com/documentation/cpp/operations_on_arrays.html#cv-dft