old-commit-hash: 538ca733c7c1640df2e42c6dad6faf6339363437
* cffi xattr function wrapper * xattr wrapper error handling * xattr tests * use xattr for tracking files uploaded * uploader xattr exception handling * update uploader tests * remove unused import * update release build * xattrs.py -> xattr.py old-commit-hash: f21d0f325e1304b08a4e05ccc6b0fe439a7e3928
old-commit-hash: e8d888c45b5cb84bf38bdb96cae579a10f7ae281