Move to Selection (SharedObjectsContainer) in reco persistency

With Rec#499 (closed) being closed since split track container MRs are in, some copying of (track) containers is being done to change persistency locations version. This is unwanted. With Selections (SharedObjectsContainers) being persistable this wouldn't be needed anymore and would improve simplicity and flexibility.

Work ongoing at LHCb!4193 (merged). After this is in, reco config (in Moore) should be adapted accordingly.