Merge pull request #13753 from theanalyst/wip/f/rgw/tagging

rgw: implement get/put object tags for S3

Reviewed-by: Adam C. Emerson <aemerson@redhat.com>
Reviewed-by: Casey Bodley <cbodley@redhat.com>

diff --cc src/rgw/rgw_op.cc
Simple merge

diff --cc src/rgw/rgw_rest_s3.cc
Simple merge

diff --cc src/rgw/rgw_rest_s3.h
Simple merge