Automatically pick the latest active index version

When using the composite node store for blue-green deployments, multiple versions of a index can exist at the same time, for a short period of time (while both blue and green are running at the same time). It is possible to select which index is active using the "useIfExists" settings in the index configurations. However, this is complicated and hard to explain / understand.

Instead, we can rely on naming patterns of the index node name. E.g.

• lucene
• lucene-2 (newer product version)
• lucene-2-custom-2 (customized version of lucene-2)
• lucene-2-custom-3 (customized again)
• lucene-3-custom-1 (newer product version)

It would be good if index selection is automatic, meaning only indexes are active that are available in the read-only repository (of the composite node store).