Combines two fibre LUTs into a single file. The LUTs must be of the same dimension, with
evenly spaced crossing angles. The LUTs must be sorted in ascending order by the crossing
angle.
EXAMPLES
Combine three LUTs (twoWatson_schemeA_snr16_inv2_{50,70,90} at crossing angles of 50, 70,
and 90 degrees.