JWT util stem to stern example

[jjg-123]

In the documentation, there is no single example of creating keys and then creating, verifying a JWT. It is stuck in bits and pieces all over the place. Also, make it easier to create a set of keys and default to using those if there are none loaded already (and, of course, a flag to replace the current keys with the new ones if needed).

[jjg-123]

PS add a note on how to show all the commands available with the /commands, as well as how to display the startup help again.