Prepare 6.2.0 M6 release
[maven-release-plugin] prepare release 6.2.0-m6
[maven-release-plugin] prepare for next development iteration
Revert "Prepare 6.2.0 M6 release"

This reverts commit 1c5f0b3644700e3221c09e0bba97acf99b24d078.
MAVEN-81 Disable XML validation so that the plugin works in offline mode