Some necessary modifications to class ElectronicStructure in order
to conform the modified projector input. In particular, the dimensions
of the projector array are now taken directly from the array,
and the old dictionary 'params' is replaced with a list 'proj_params'
containing information on the character of projectors.
Small fixes to accord with the changes of Vaspio:
* 'nspin' is now taken from Eigenval.ispin
* 'nc_flag' is now determined from the value of 'ncdij' read from DOSCAR
* 'ferw' is now taken from Eigenval
The files from the original vasp-interface repository are reshuffled in
accord with the directory structure of dft_tools. Some of the directories,
such as 'test' (unit tests for the interface), 'examples' (simple examples for
the development purposes) are temporarily placed into 'python/vasp' directory
to avoid confusion with integral tests and examples of dft_tools.