[maven-release-plugin] copy for tag v2.6.8

[maven-release-plugin] copy for tag v2.6.7

[maven-release-plugin] copy for tag v2.6.6

[maven-release-plugin] copy for tag v2.6.5

[maven-release-plugin] copy for tag v2.6.4

[maven-release-plugin] copy for tag v2.6.3

[maven-release-plugin] copy for tag v2.6.2

[maven-release-plugin] copy for tag mxcache-2.6.1

[maven-release-plugin] copy for tag mxcache-2.6.0

[maven-release-plugin] copy for tag mxcache-2.5.12