[maven-release-plugin] copy for tag pmd_releases/6.0.0

[maven-release-plugin] copy for tag pmd_releases/5.8.1

[maven-release-plugin] copy for tag pmd_releases/5.8.0

[maven-release-plugin] copy for tag pmd_releases/5.7.0

[maven-release-plugin] copy for tag pmd_releases/5.6.1

[maven-release-plugin] copy for tag pmd_releases/5.5.7

[maven-release-plugin] copy for tag pmd_releases/5.6.0

[maven-release-plugin] copy for tag pmd_releases/5.5.6

[maven-release-plugin] copy for tag pmd_releases/5.5.5

[maven-release-plugin] copy for tag pmd_releases/5.4.6