paxtar

paxtar is a copy of Go's archive/tar package from Go 1.7.3. The only difference is the addition of the NewPaxWriter function to writer.go. This function can be used to create a Writer that always prefers using PAX headers. Although the PAX standard is slightly less compatible (defined in 2001), it is still widely used, and always using PAX headers resolves issues such as golang/go#17630.