23:12 rodrigo 

Add new port math/nfft

NFFT is a software library, written in C, for computing non-equispaced fast
Fourier transforms and related variations. It implements the following
transforms:

1. Non-equispaced fast Fourier transform (NFFT)
 - forward transform (NFFT), i.e. frequency to time/space domain
 - adjoint transform (adjoint NFFT), i.e. time/space to frequency domain

2. Generalisations
 - to arbitrary nodes in time and frequency domain (NNFFT)
 - to real-valued data, i.e. (co)sine transforms, (NFCT, NFST)
 - to the sphere S^2 (NFSFT)
 - to the rotation group (NFSOFT)
 - to the hyperbolic cross (NSFFT)
3. Generalised inverse transformations based on iterative methods, e.g.
   CGNR/CGNE

PR:		223429
Submitted by:	Michael Danilov <mike.d.ft402@gmail.com>