cli/commands: Help for multiple word command did not show properly.

cli/commands: Help for multiple word command did not show properly.

Possible commands are stored as keywords, each keyword has its own structure.
The last acceptable keyword structure contains string with hint. But when the hint was printed only direct child
of the base keyword was considered. If it was multi keyword command, the first child did not carry any hint to print,
so it was ignored.

Now, if we don't find a hint in a child, we recursively search in grandchildren.