Adding ".seg" to X-Object-Manifest value (fixed #268)

The Openstack Proxy server needs to list out just the segments when it computes the ETag in response to a GET/HEAD on a manifest file. If the X-Object-Manifest is just the object name the Proxy server matches the segments and the manifest which cause the Proxy to create a bad ETag
Fixed typo in objectManifestValue definition
Merge pull request #269 from its-not-a-bug-its-a-feature/patch-1

Adding ".seg" to X-Object-Manifest value (fixed #268)