72x taus sqlite hook

The hooks for the sqlite file reading that have been originally in #4585. There have been reported differences in anti-electron config, that have been caused by typo in config files and fixed. The difference in isolation discriminators was not observed, so perhaps it have been fixed already.

This pull request does not change the RECO sequence at all, but adds new function to switch MVA input to a DB file
I *think* that intention of the author (@veelken) was to save the object throughout the processing, so one does not need to read it in every event. But if the destructor is called only at the end of running, than this change should be reverted indeed.