updated docs and scripts

Updated docs

Changed tkgui.properties.XrayInteractionsGUI to run independantly.

Added cli arguments to run xray properties gui and fdmnes gui.

Version 3.3.2

replaced np.NAN with np.nan

Merge pull request #26 from DanPorter/new_cell_basis

New cell basis

Merge remote-tracking branch 'origin/master'

Version 3.0.0

Large feature update. New GUI features:
 - New diffractometer mode in GUI
 - New ability to simulate diffractometer detectors
 - updated Scattering GUI including electron and neutron wavelengths
 - Unit converter, space group checker etc.
Updates
 - Correction to powder: Thanks Sergio I. Carvajal!
 - Correction to x-ray dispersion sign, thanks Anuradha Vibhakar!
 - Included new wavelength calculations in functions_crystallography.py
 - other minor improvements

Version 2.2.3

Updated docs and added binder link

Version 1.8.2

Magnetic spacegroup positions added, write_mcif added, various improvements. Tensor_Scattering removed.

Added powder averaging, changed scattering gui, added multicrystal

Added powder averaging, changed scattering gui, added multicrystal