A lot of image filename and paths are used unquoted.  Quote these to
make sure that directories / filenames with spaces are not problematic.
Signed-off-by: NJeff Cody <jcody@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>