[maven-release-plugin] copy for tag jenkins-1.526

[maven-release-plugin] copy for tag jenkins-1.525

[maven-release-plugin] copy for tag jenkins-1.524

[maven-release-plugin] copy for tag jenkins-1.523

[maven-release-plugin] copy for tag jenkins-1.522

[maven-release-plugin] copy for tag jenkins-1.521

[maven-release-plugin] copy for tag jenkins-1.509.2

[maven-release-plugin] copy for tag jenkins-1.520

Revert "Moving on to 1.509.3 while I solicit feedback on 1.509.2 rele…

…ase plan."

This reverts commit f6a4832.
This branch now becomes 1.509.2

[maven-release-plugin] copy for tag jenkins-1.519