[JENKINS-24376] [JENKINS-19977] Switch Run.id format to use milliseconds and UTC

[JENKINS-24376](https://issues.jenkins-ci.org/browse/JENKINS-24376) and [JENKINS-19977](https://issues.jenkins-ci.org/browse/JENKINS-19977).

Probably need to put in forward-looking compatibility fixes into several plugins before this could be safely merged.