* Ask openstacksdk to log to stderr instead of stdout, otherwise its
warnings break parsing the output.
* Respect the --verbose flag (same as --debug but without tracebacks).
* Do not propagate log records that are handled by either openstacksdk's
or ours logging code.
Change-Id: Ia191ab32f0d4f8f50cb266332d4f4bc96619cb58