If triggered build is from FlowRun type, then iterate through its jobs graph adding all downstream jobs build urls to the message that will be posted to github pull request.

Please review my changes, and consider changing what you think it's better for the plugin. I'm not sure if I could have achieved this in a easier/extensible way, so please send me your feedback about how to do it. Thanks in advance
I'm not sure the best way to do this, but you can add an optional flag here, but then you'll need to check if that plugin is in installed w/o gettting a NoClassDefFoundException.