Move pkg/archive out of main module/repository

[dmcgowan]

Description

Summary

Move pkg/archive out of the main module into its own repository

Currently relevant dependencies

github.com/docker/docker/pkg/archive
  ├ github.com/docker/docker/pkg/idtools
  ├ github.com/docker/docker/pkg/ioutils
  ├ github.com/docker/docker/pkg/pools
  ├ github.com/docker/docker/pkg/system
  ├ github.com/moby/patternmatcher
  ├ github.com/moby/sys/sequential
  └ github.com/moby/sys/userns

github.com/docker/docker/pkg/idtools
  └ github.com/moby/sys/user

github.com/docker/docker/pkg/ioutils (nothing relevant)

github.com/docker/docker/pkg/pools
  └ github.com/docker/docker/pkg/ioutils

github.com/docker/docker/pkg/system (nothing relevant)

Proposal and steps

• Copy relevant pkg/system functionality Decouple pkg/archive from pkg/system #49072
• Remove parts of pkg/system only used for archive, pkg/system is not suitable for standalone library since most of the functionality is considered temporary until officially supported. pkg/system should become internal.
• Copy relevant pkg/ioutils, only used for one simple thing Decouple pkg/archive from pkg/ioutils #49073
• Copy relevant parts of pkg/pool to archive or move pool
• Move pkg/idtools under github.com/moby/sys Split idtools to an internal package and package to be moved #49087
• Remove uses of pkg/errors pkg/archive: replace uses of pkg/errors for stdlib errors #49101
• Move pkg/archive to a new repository under github/moby

[thaJeztah]

Related / prior ticket;

• Move pkg/archive and dependencies out into their own repositories #21700
• related (epic); Find a place for /pkg #32989

[dmcgowan]

I think you could close those older issues.

Do the steps I outline sound reasonable to you? I'll open them one at a time to make sure it make sense along the way and I can turn this issue into check boxes.

[thaJeztah]

Also opened a PR to remove use of pkg/errors; most errors were already using stdlib, and only 2 or 3 locations used pkg/errors; #49101