CHANGELOG: add changelog for v2.1.5 (pingcap#9501)

changelog: add release note v2.1.4 (pingcap#9312)

CHANGELOG: add release notes for v2.1.3 (pingcap#9174)

*: add release note 3.0.0-beta to CHANGLOG.md (pingcap#9117)

rebase release-2.0 to release-2.0-binlog (pingcap#8928)

CHANGELOG: add changelog for v2.0.11 (pingcap#8925)

binlog: use pumps client to write binlog (pingcap#7659) (pingcap#8078) (

pingcap#8822)

CHANGELOG: add changelog for v2.1.2 (pingcap#8767)

CHANGELOG: add release note for v2.0.10 (pingcap#8721)

doc: add the change log for release 2.1.1 (pingcap#8666)