from SHMS shower counter. Make THcShowerArray a friend class to
THcShower in order to have access to the debug flags.

  Base class THcRawHit has null GetReference method.  Returns
  zero.
  THcRawDCHit will get the reference time if it was specified in the map file.
  It is up to the detector class to use the reference time to subtract off
  pipeline TDC jitter.

  In the map file, use
    slot=<slot>,<refchan>
to specify the reference channel for that slot.  If the slot= directive
is repeated, the reference channel number must be given for each repeat.
(Could potentially have different reference channels for different channels
of that slot.)

  Enable by defining HITPIC in THcShowerArray.h

  GetData accepts a pedestal range and an integration range.
  Samples in the integration range are added after subtracting the
  average of the pedestal range from each sample.
  Method also provided to return dynamic pedestal

  A shower counter hit can now be multiple samples, with a different
  number of samples allowed for positive and negative tubes.
  GetData(signal) now returns the sum of all the samples.  This should
  still be compatible with fastbus ADCs as they are a single sample
  (which is already the integral.)

  Added as an optional sub detector THcShowerArray to the THcShower class
  Get hit data with GetData method instead of hit member variables
    so as to be compatible with FADC compatible hit list

  Fix fptime formulae in output.def
  Remove unused parameter from THcHodoEff
  Remove undefined parameter from report.def

  Method for number of planes
  Method for list of plane objects
  Method to return "good" flags for given track, plane and counter

  Makefile and THcInterface changes to reflect the changes in podd
  scaler code

in THcScintillatorPlane