ENH: Refactor SlicerWizard logging

Convert SlicerWizard reporting to use Python's built-in logging
facility, and add additional debug messages (newly controlled by the
--debug option).

This gives us additional features and better control over logging, e.g.
we now implicitly use logging levels, with WARNING and higher going to
stderr, and INFO/DEBUG going to stdout, as well as applying text
wrapping to everything.

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22965 3bd1e089-480b-0410-8dfb-8563597acbee