Points2mult.m

Computes multipole moments from a set of point charges Parameters:

   xyz    - coordinates as [x y z] with multiple rows,
            at which density rho is evaluated, in Angstroms.

   mxyz   - paramagnetic centre coordinates as [x y z], in 
            Angstroms.

   L      - array of ranks of spherical harmonics of the density

   rho    - column of the destity at the points xyz

   method - 'points' or 'grid'. 'Grid' integrates with corresponding d3r
            and 'points' just sum the density at points. 

Output:

   Ilm    - predicted multipole moments of the density