With a multipart-manifest PUT request, if client sends the md5 of the
segments' etags, a 422 Unprocessable Entity response is returned. This
patch fixes that and confirms the etag
Change-Id: I4598a2a3f16ca8727bb07bbb6d8efcfcae777796
Closes-Bug: #1213200
Co-Authored-By: Tim Burke <tim@swiftstack.com>