Plot dataset coming from individual monochromatic OIFits with colors

[gmella]

Is your feature request related to a problem? Please describe. I would like to look at wavelength distribution plotting data from a collection of monochromatic OIFIts. At present time all measurement points are shown in black.

Describe the solution you'd like I would like to get the last new cool colormap to plot all data even if they come from monochromatic individual data files

Additional context Here comes a good test collection : https://oidb.jmmc.fr/search.html?collection=~J%2FA%2BA%2F593%2FA45

[bourgesl]

Fixed cases:

• many 1 channel files (vega)
• mixed 1 channel file (pionier or iota) with other instruments

[gmella]

I checked your new code which provides beautiful colors :) Thx !