Describe y create_object_metadata accepts 2 types

Answers questions in review comments posted against:
http://review.gluster.org/6157

Signed-off-by: Peter Portante <peter.portante@redhat.com>

Change-Id: I96b348b4f54eaeb0d5d641af88cfcbfe961e4950
Reviewed-on: http://review.gluster.org/6161
Reviewed-by: Luis Pabon <lpabon@redhat.com>
Tested-by: Luis Pabon <lpabon@redhat.com>
Rebase to lastest OpenStack Swift DiskFile API

As of October 28th, 2013, we rebase to OpenStack Swift master (commit
4bfe674) to pick up the lastest officially supported DiskFile API
changes. We use a snapshot of OpenStack Swift stored in the
gluster-swift launchpad downloads area so that we can deliberately
rebase at our own pace.

With this refactoring, all the code for handling I/O is wholly
contained in the swift tree for object operations. This will allow us
to use a different fs_utils implementation in the future (for example,
one based on a yet-to-be-implemented python bindings over libgfapi).
This also means the "Fake_file" class has been removed entirely.

Change-Id: I767983f88c59786e30b6c64da16d1cb6ab3c3e7f
Signed-off-by: Peter Portante <peter.portante@redhat.com>
Reviewed-on: http://review.gluster.org/5993
Reviewed-by: Luis Pabon <lpabon@redhat.com>
Tested-by: Luis Pabon <lpabon@redhat.com>