Fix reading xattrs in object-server's unittests.

Use for reading metadata in unit tests function from object-server.

Change-Id: I2bfeb76fdd775442a0e614fef740b0987fba4a22
Fixes: bug #1079131
Fix container-server sorting for manifest listings.

The current code will always contact the container server for the
first replica of the container; this fixes it to use the same
backend-sort as all the other places in the proxy that talk to
backends.

Change-Id: If1c168b95bfc5cd120036869f3066549b7a1000a
SLO multipart-manifest=get returns incorrect Content-Type

Change-Id: I657c9f7a7555d90ccfa7e6ff0f5f3fcbd7eada1d
Change setup.cfg style.

Change-Id: I466470237ddd317740eb99bd55af7e7a50270ae3
Fixes: bug #1163258
Update documentation for account_quota middleware

Change-Id: I3dc7930ee2a1eb26b1f60e83fce2bc1bea0a8b0f
Merge "Change setup.cfg style."
Merge "SLO multipart-manifest=get returns incorrect Content-Type"
Merge "Fix reading xattrs in object-server's unittests."
Merge "Fix container-server sorting for manifest listings."
Merge "Update documentation for account_quota middleware"