Project cbi.p2repo.aggregator_gerrit

Job to run a build of CBI aggregator based on a Gerrit patch.

• Don't run org.eclipse.cbi.p2repo.aggregator/org.eclipse.cbi.p2repo.releng.parent/buildScripts/runBuild.sh and directly call Maven instead.
• Don't sign jars, since it's not necessary for a Gerrit triggered build.
• Run org.eclipse.cbi.p2repo.aggregator/org.eclipse.cbi.p2repo.releng.parent/buildScripts/testOurRepo.sh.

This job replaces cbi.p2repo.aggregator_gerrit_legacy.