doc: update rbd man page for new options

--no-progress and --allow-shrink were added recently.

Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
man: refresh content from rst

Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
man: update remaining copyright notices

Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
Merge pull request #249 from ceph/wip-cuttle-man

man page updates

Reviewed-by: Sage Weil <sage@inktank.com>