0.2.5
 - fix: make sure the reference QLSI image is treated exactly like
   the data QLSI image in terms of padding and subtracting mean
0.2.4
 - enh: allow to specify approximate padding size in FFTFilter
 - docs: update wrong docs stated padding with linear ramp, but
   we are doing zero-padding
0.2.3
 - fix: allow computation of QLSI wavefront without reference image
 - ref: turn field into a property and let subclasses define how to
   compute phase and amplitude
0.2.2
 - enh: use multiprocessing.cpu_count() as threads argument for FFTW
0.2.1
 - ref: invert phase by multiplying field.imag by -1 in OAH
0.2.0
 - feat: add quadri-wave prototype for quadriwave lateral shearing
   interferometry (subject to future refactoring and breaking changes)
 - feat: implement FFT with PyFFTW
 - setup: remove unused install_requires
 - ref: clean up BaseInterferogram and support passing pipeline
   keyword arguments during init
0.1.2
 - ref: add base class for Fourier hologram analysis
0.1.1
 - fix: some Fourier filters did not work properly due to earlier
   refactorization
 - enh: support hologram data that are RGB(A) (by only taking R)
 - tests: imported tests from qpimage
0.1.0
 - initial release
