Bug#947782: ITP: go-containerregistry -- Go library and CLIs for working with container registries

["James Montgomery" <james@onedev.org>]

Package: wnpp
Severity: wishlist
Owner: James Montgomery <james@onedev.org>

* Package name    : go-containerregistry
  Version         : 0.0~git20191218.34fb8ff-1
  Upstream Author : Google
* URL             : https://github.com/google/go-containerregistry
* License         : Apache-2.0
  Programming Lang: Go
  Description     : Go library and CLIs for working with container registries

 go-containerregistry Build Status
 (https://travis-ci.org/google/go-containerregistry) GoDoc
 (https://godoc.org/github.com/google/go-containerregistry) Go Report
 Card (https://goreportcard.com/report/google/go-containerregistry)
 Code Coverage (https://codecov.io/gh/google/go-containerregistry)
 Introduction This is a golang library for working with container
 registries.  It's largely based on the Python library of the same name
 (https://github.com/google/containerregistry).
 .
 The following diagram shows the main types that this library handles.
 OCI image representation Tools This repo hosts some tools built on top
 of the library.  crane crane (cmd/crane/doc/crane.md) is a tool for
 interacting with remote images and registries.  Installation
 .
 GO111MODULE=on go get -u github.com/google/go-containerregistry/cmd/crane
 .
 Images You can also use crane as docker image
 .
 ```sh $ docker run --rm gcr.io/go-containerregistry/crane ls ubuntu
 .
 2019/12/03 09:33:01 No matching credentials were found, falling back on
 anonymous 10.04 12.04.5 12.04 12.10 ```
 .
 And it's also available with a shell, which uses the debug tag
 .
 sh docker run --rm -it --entrypoint "/busybox/sh"
 gcr.io/go-containerregistry/crane:debug
 .
 gcrane gcrane (cmd/gcrane/README.md) is a GCR-specific variant of crane
 that has richer output for the ls subcommand and some basic garbage
 collection support.  Installation
 .
 GO111MODULE=on go get -u github.com/google/go-containerregistry/cmd/gcrane
 .
 Images You can also use gcrane as docker image
 .
 ```sh $ docker run --rm gcr.io/go-containerregistry/gcrane ls ubuntu
 .
 2019/12/03 09:33:01 No matching credentials were found, falling back on
 anonymous 10.04 12.04.5 12.04 12.10 ```
 .
 And it's also available with a shell, which uses the debug tag
 .
 sh docker run --rm -it --entrypoint "/busybox/sh"
 gcr.io/go-containerregistry/gcrane:debug
 .
 k8schain k8schain (pkg/authn/k8schain/README.md) implements the
 authentication semantics use by kubelets in a way that is easily
 consumable by this library.
 .
 k8schain is not a standalone tool, but it's linked here
 for visibility.  Debug images for crane and gcrane crane and
 gcrane also provide a debug image (containing a shell), which
 can be found at • gcr.io/go-containerregistry/crane:debug•
 gcr.io/go-containerregistry/gcrane:debug Inside these images, crane and
 gcrane can be used like this:
 .
 sh /ko-app/crane cp ...
 .
 Emeritus: ko (https://github.com/google/ko) This tool was originally
 developed in this repo but has since been moved to its own repo.

Reasoning:
go-containerregistry is a dependency for container-diff (https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=945524)