Common: session renew command

[MikeTheSnowman]

Currently session durations are rather short (only one day). I think it might be a nice feature to have a fcli ssc session renew command that will work in the following way:

• If the user had previously logged in to a session using their user credentials (username/password), then the renew command should just ask the user for a password to generate a new token in order to renew the session.
• If the user had previously logged in to a session using a token, then renew will simply ask for a new token.