THcTimeSyncEvtHandler can correct runs where the 1190's in a crate
  go out of sync because of a large event.  (This would happen in the
  spring of 2018.  Should be fixed in the DAQ now.)  It a previous version
  this sync problem was detected by looking for 1190 banks that were too large.
  In this update, the first event is used to make a list of which slots
  have TDCs in them.  For subsequent events, it checks that every TDC slot
  has a header and trailer word in the bank.  If any TDCs are found to be
  missing, and the bank size is above a threshold, subsequent events are
  presumed to be out of sync and corrected for in the filtered run output file.

  THcTimeSyncEvtHandler is a toolbox to study and correct various
  synchronization issues.
  It checks that the timestamp in the FADC250s agrees with the timestamp
  in the TI modules.
  It also checks if the event counter in the 1190 modules agrees with the
  event counter in the TI modules.
  It can be used to correct the 1190 synchronization problem we have
  seen in ROC3 by writing out a corrected data file.  See the next commit
  for an example of how it is used.

  This event type handler can be used to gather statistics on the slippage
  of trigger times in FADC250 headers.
  It looks at the relative trigger times between the ADCs and the TI modules
  and counts the number of times the relative times shift.

  The ADC trigger times will have a small offset relative to the TI trigger
  times.  The method AddExpectedOffset(roc, offset) allows the setting
  of this offset on a crate by crate basis.  If expected offsets are not
  set, the first event is used to determine the offsets.