[#66658104] Add --quiet and --verbose options

This PR adds --quiet and --verbose options:

* --quiet suppresses all output bar error messages and the Fog task progress bar (if enabled)
* 'normal' operation now displays info messages and above. The progress bar is still displayed.
* --verbose operation displays debug messages too. A tandem update to Vcloud::Core changes the level of all 'sub-operations' like CPU/memory update to be at this level.

NB: The code surrounding disabling the Fog progress bar has been pulled from this PR, I'll push it up as a separate PR for discussion.