Merge branch 'wip-sts-authorization'

Merge pull request #14307 from adamemerson/wip-sts-authorization

common: Add make_unique
submodule: Tencent's RapidJSON library
common: Add ISO-8601 Date Support
rgw: Add is_identity to AuthApplier class
rgw: Move globbing flags to header
buffer: Make the use of static areas more convenient
rgw: Add basic support for IAM policies
rgw: Build bucket permission and environment in req_state
rgw: Verify policies as WELL as ACLs
rgw: RESTful bucket policy ops
rgw: Write documentation for bucket policies

Reviewed-By: Casey Bodley <cbodley@redhat.com>
Reviewed-By: Radoslaw Zarzynski <rzarzynski@mirantis.com>
Reviewed-By: Kefu Chai <kchai@redhat.com>