lev00 and SIESTA

Basically, the following functionality is supported at the moment:

• Total electronic density
• Spin density

Actually, it covers nearly all of the lev00 functionality related to densities.

An auxiliary utility get_param_siesta will be needed (supplied) to work out some necessary information from the SIESTA output as well as its input files. This additional utility is described in the next Section 5.2.1.