MS_CIJ2CIJKL - Convert from Voigt elasticity matrix to tensor

Converts between a a 6x6 Voigt representation and a 3x3x3x3 tensor
    representation of anisotropic elasticity.

[CC] = MS_cij2cijkl(C)

Usage:
    C must be a rank 2 array with size (6,6). The returned array C will
    be rank 4 with size (3,3,3,3).

Notes:
    Do not use this function for the elastic compliance as additional
    terms are needed in this case.

See also: MS_cijkl2cij