Usage:
  mode
  mode <which>

The 'mode' command controls the current mode of the psiTurk
shell. Type 'mode live' or 'mode sandbox' to switch to either mode, or
simply 'mode' to switch to the opposite mode. Changing mode has no
effect on existing HITs, but controls whether future commands operate
live or in the Worker Sandbox. For example, if you create a HIT while
in 'sandbox' mode, and then switch to 'live' mode, the created HIT
will remain in the Worker Sandbox. But if you now create a second HIT,
it will appear on mTurk for live workers to complete. Similarly,
commands like 'worker list' or 'hit list all' will list sandbox
workers and HITs while in sandbox mode, and will list live workers and
HITs while in live mode.

