support Field Distribution for 1D and 2D (Not for 1D_conical). fixed setup.py not to contain other folders than meent.
0.4.2
bug fix: change setup.py so that it contains nk_data folder. change argument 'wls' to 'wavelength' since Meent instance changed to deal with only on single wavelength.
0.4.1
Adding a method creating unit cell with objects.
0.4.0
change Fourier Transform from DFT to CFT. Using Fourier Transform on piecewise constant function can save memory.