Adds a new form of system metadata for objects.
Sysmeta cannot be updated by an object POST because
that would cause all existing sysmeta to be deleted.
Crypto middleware will want to add 'system' metadata
to object metadata on PUTs and POSTs, but it is ok
for this metadata to be replaced en-masse on every
POST.
This patch introduces x-object-transient-sysmeta-*
that is persisted by object servers and returned
in GET and HEAD responses, just like user metadata,
without polluting the x-object-meta-* namespace.
All headers in this namespace will be filtered
inbound and outbound by the gatekeeper, so cannot
be set or read by clients.
Co-Authored-By: Clay Gerrard <clay.gerrard@gmail.com>
Co-Authored-By: Janie Richling <jrichli@us.ibm.com>
Change-Id: I5075493329935ba6790543fc82ea6e039704811d