process: remove cryptic TFile handling
BUGFIX: fix drift hits double counting

For details, see apropriate lab journal record.
StdHits: refactor from TrkRecogH and StdDrift bits

StdHook does more than StdDrift, but we can later introduce template
parameters to allow user restrict hits to prop or drift hits to get a
better performance.
StdHits: do drift calibration in handle_drift_data