Enable PFlow jets in tauRec with option to use shower subtracted clusters

This is a follow-up of !31803 (closed) and was discussed in: https://its.cern.ch/jira/browse/ATLTAU-1691

Now it properly supports the use of shower subtracted clusters. A fix was required in eflowRec which is already in master. There were also a few places in tauRec that had been updated since then, so I decided to start this new merge as it will be much tidier.

The function in HelperFunctions has returns a list of clusters from the jet constituents. For the neutral PFOs the option changes whether it returns the shower-subtracted clusters or not. Then it adds any calo clusters from charged PFOs, checking for duplicates. For LC topo jets it simply retrieves the cluster from the jet constituent.

The default behaviour is still set to use LCTopo jets and not use the shower subtracted clusters, this is because a flag needs to enabled in eflowrec to use this. There is an flag to enable including the subtracted clusters in tauRecFlags.

There is a slight change to the dR check in MvaTESVariableDecorator, it now uses the cluster object rather than the jetconstituent. The function is now used in TauElectronVetoVariables too.