Add a script to convert coefficients in OSKAR csv format to EveryBeam-OSKAR hdf5 format.

Currently the repository contains a script to convert from Matlab to hdf5 format. There is also a matlab script to generate a OSKAR csv file from a Matlab file.

The original Matlab file for a given csv file, is not always available. In that case the hdf5 file needs to be generated from the csv file.

A test should confirm that the Matlab -> csv -> hdf5 route has the same result as the Matlab -> csv route.