pycfitsio: Python ctypes wrapper for cfitsio

Features:

* read binary tables using hdu and column names into simple dictionaries of arrays
* write FITS files incrementally 1 HDU at a time

Example:

    import pycfitsio

    f = pycfitsio.open("test/data.fits")

    hdulist = f.HDUs

    print(hdulist)
    OrderedDict([('DATA', HDU: DATA)])

    hdu = f['DATA']

    column_array = f['DATA'].read_column('signal')

    all_columns = f['DATA'].read_all()
    print(all_columns)
    OrderedDict([('signal', array([   0., 1. ....])), 'flag', array([1, 1, ....])])