Support baseline replacement for all repositories with jar-signed content

[merks]

These sites with jar-signed content should do baseline replacement:

• https://download.eclipse.org/tools/orbit/simrel/maven-bnd/
• https://download.eclipse.org/tools/orbit/simrel/maven-sign/
• https://download.eclipse.org/tools/orbit/simrel/orbit-legacy

This site does not need that because does not modify the direct-from-maven artifacts:

• https://download.eclipse.org/tools/orbit/simrel/maven-osgi/

The aggregation consumes from the sites above so does not need special handling because it aggregates already-baseline-replaced content:

• https://download.eclipse.org/tools/orbit/simrel/orbit-aggregation/

[merks]

Initially each did a nightly build with a baseline replace of the corresponding latest release and now, going forward, each will do nightly/milestone builds with a baseline replace of the corresponding latest night build. As such, any new artifacts or modified artifacts will be produced once the first time by a nightly build and will be baseline replaced from that point on.