clean up EMPFlowAll config

This MR aims to reduce the size of the ntuples dumped with the EMPFlowAll config.

The modifications introduced by this MR touch mostly the EMPFlow configs:

Now, three configs are introduced.

1. EMPFlowSlim.json: contains no track information, dumps basic quantities defined in single-btag-variables.json and in addition the already evaluated tagger scores for rnnip, DL1r, dipsLoose, and DL1dv00
2. EMPFlow.json: contains only loose track information, dumps detailled quantities defined in single-btag-variables-all.json, including all recent taggers default config for group productions
3. EMPFlowTruth.json: extends EMPFlow.json by truth particle information dumped in addition

Closes #69 (closed)