file_io handles sextractor header

[lbaumo]

Summary

This allows get_header in file_io to convert the fits_ldac header, stored as a binary table, from sextractor to a dictionary. It also corrects the documentation for get_header. This is the first step in addressing #632 as well as #616 and #604.

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[martinkilbinger]

Looks good, maybe you can run black on the modified files for automatic formatting.

[lbaumo]

what is going on with the CI tests? It looks like installation is failing.

[martinkilbinger]

what is going on with the CI tests? It looks like installation is failing.

Looks like a version conflict between numba and numpy. I had to upgrade numpy to a newer version due to some conda errors. Try to set numba=0.58.1.

There might be other CI errors, this has not been working for quite some time.