Prepare v0.5.1 release

Author: calind

Changelog.md

@@ -4,8 +4,13 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/), and this project
 adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-
 ## [Unreleased]
+### Added
+### Changed
+### Removed
+### Fixed
+
+## [0.5.1] - 2021-10-12
 ### Added
  * Add `orchestrator.persistence.fsGroupWorkaroundEnabled` for persistent volume
    provisioners wich don't support fsGroup in security context (fixes #615)