Please add Cuban .cu domains support

[elierpg]

I tested the library with a Cuban .cu domain, but it was unable to retrieve any details. There is a public website called Cubanic(https://www.nic.cu) that allows you to look up information about .cu domains. It would be useful to integrate this source into the library to improve data extraction functionality for .cu domains.

Reference:

Public website: https://www.nic.cu

Thank you for your attention.