Update version to 2.7.0-rc.0

Signed-off-by: Derek McGowan <derek@mcgstyle.net>

Add release notes for 2.7.0 release candidates

Update release documents

Remove redundant AUTHORS file in favor of relying
on .mailmap for keeping track of author names.
Move older changelogs to release directory.
Move release checklist to releases README.

Signed-off-by: Derek McGowan <derek@mcgstyle.net>

Signed-off-by: Derek McGowan <derek@mcgstyle.net>

Signed-off-by: Derek McGowan <derek@mcgstyle.net>

Fix some typos

Signed-off-by: Rui Cao <ruicao@alauda.io>

remove dependencies on resumable

typo fix from existant to existent

Signed-off-by: liyongxin <yxli@alauda.io>
Signed-off-by: Yongxin Li <yxli@alauda.io>

Signed-off-by: David Wu <david.wu@docker.com>

Signed-off-by: David Wu <david.wu@docker.com>

Signed-off-by: David Wu <david.wu@docker.com>

Signed-off-by: David Wu <david.wu@docker.com>

Fix some typos

Signed-off-by: David Wu <david.wu@docker.com>

Signed-off-by: David Wu <david.wu@docker.com>

Signed-off-by: ruicao <ruicao@alauda.io>

Improve gcs driver

Fix registry stripping newlines from manifests

Signed-off-by: Huu Nguyen <whoshuu@gmail.com>

Signed-off-by: Huu Nguyen <whoshuu@gmail.com>

Signed-off-by: Huu Nguyen <whoshuu@gmail.com>

Signed-off-by: Andrey Kostov <kostov.andrey@gmail.com>

Signed-off-by: Andrey Kostov <kostov.andrey@gmail.com>

Signed-off-by: Andrey Kostov <kostov.andrey@gmail.com>

Ignore missing paths during enumeration

Update ncw/swift Vendor Package

Content must be preserved exactly

Signed-off-by: Derek McGowan <derek@mcgstyle.net>

It's possible to run into a race condition in which the enumerator lists
lots of repositories and then starts the long process of enumerating through
them. In that time if someone deletes a repo, the enumerator may error out.

Signed-off-by: Ryan Abrams <rdabrams@gmail.com>

Signed-off-by: Corey Quon <corey.quon@gmail.com>

Signed-off-by: mlmhl <409107750@qq.com>

fix gometalinter

Signed-off-by: David Wu <david.wu@docker.com>

Create and populate htpasswd file if missing

Add configurable layers in manifest events

Graceful shutdown

Signed-off-by: Manish Tomar <manish.tomar@docker.com>