Update deploy-nuxeo.com-site Job to Pipeline script

The www.nuxeo.com Jenkins Job would benefit us by being converted to a pipeline script.

All other settings should be kept as they are ideally.

static.nuxeo.com Job is a good example of what we're looking for from the job.

If this is something I can do without losing any of the webhooks etc, please point me in the right direction, I'm happy to write the pipeline script and put it in the nuxeo.com repository (JenkinsFiles/build.groovy)

Thanks in advance.