nr-cli documentation

[thatsdone]

Hi,

This is a question and a suggestion (depending on the answer to the question).

UERANSIM includes a cli 'nr-cli', and is this (nr-cli) a supported feature?

If yes, it's better to add documentation of nr-cli, IMHO.
Also, I think I can make some contributions to the document and report some issues that I noticed while playing with nr-cli.