Work-around for RGW failing to send IsTruncated on listing all keys.
Work-around for RGW failing to send IsTruncated on listing all keys.

Without this, it fails to delete the bucket when there's more than 1000 keys.

smithfarm/s3-tests,basho/s3-tests,jmunhoz/s3-tests,timuralp/s3-tests,Nexenta/s3-tests,tobegit3hub/s3-tests,piousbox/s3-tests,ceph/s3-tests,Intel-bigdata/s3-tests,Nexenta/s3-tests,SUSE/s3-tests,Nexenta/s3-tests,piousbox/s3-tests,smithfarm/s3-tests,dreamhost/s3-tests,Intel-bigdata/s3-tests,dreamhost/s3-tests,robbat2/s3-tests,piousbox/s3-tests,timuralp/s3-tests,Nexenta/s3-tests,andrewgaul/s3-tests,basho/s3-tests,ceph/s3-tests,robbat2/s3-tests,andrewgaul/s3-tests,SUSE/s3-tests,jmunhoz/s3-tests,tobegit3hub/s3-tests