Show commands description

[piotrooo]

When a command description is not defined, we should not display N/A or empty parentheses ().

BTW, why are we displaying the text in parentheses (the grey one)? It seems to be duplicated.

[fmbenhassine]

The "N/A" is added because it is better than nothing. However, IIRC, we do not add (), this is a JLine thing.