Add support for Groovy Postbuild plugin v2.0+
Add support for Groovy Postbuild plugin v2.0+

From https://plugins.jenkins.io/groovy-postbuild/:
> From version 2.0, Groovy Postbuild plugin introduces Script Security
> Plugin.

This change adds support for the markup generated by the plugin in v2.0+.

Also got rid of the useless 'continue' statement which was silently
ignoring unknown markup, rather than letting the wrecker convert it into
raw XML.

ktdreyer/jenkins-job-wrecker