Zeroturnaround JRebel update site no longer exists; automated Central install broken for 4 current versions of Central

09:26:43    [p2.dir] !ENTRY org.eclipse.equinox.p2.artifact.repository 4 1000 2016-04-09 09:26:43.985
09:26:43    [p2.dir] !MESSAGE No repository found at http://update.zeroturnaround.com/update-site-jboss/.

So, we need to use an alternate update site, such as the one linked from Eclipse Marketplace, eg., http://update.zeroturnaround.com/update-site/

And we need to verify that the features we include in Central are still available on the new site.

Affected jobs:

http://jenkins.mw.lab.eng.bos.redhat.com/hudson/view/DevStudio/view/DevStudio_9.0.mars/job/jbosstools-install-grinder.install-tests.matrix_4.3.mars/
http://jenkins.mw.lab.eng.bos.redhat.com/hudson/view/DevStudio/view/DevStudio_9.0.mars/job/jbosstools-install-p2director.install-tests.matrix_4.3.mars/