New class THcDC is whole set of wire chambers.
  THcDriftChamber is one chamber (6 planes)
  Implement space point finding from h_pattern_recognition up to point
     before where space point lists from the two chambers are combined.
  Includes
      FindEasySpacePoint   (h_find_easy_space_point)
      FindHardSpacePoints  (find_space_points)
      DestroyPoorSpacePoints (h_sp_destroy)
      SpacePointMultiwire  (h_sp_multiwire)
      ChooseSingleHit 	   (h_choose_single_hit)
      SelectSpacePoint	   (select_space_points)

Space points are arrays of structures in the THcDriftChamber class.  Will
probably need to take space points out class so that they can be looked at
at the THcDC level.

New code is only tested to see that it compiles and that space points
are sometimes found.

GN: finished debugging the hodoscope start time calculation. Results match 1-to-1 the corresponding "engine" result.

Started with Simon's code, but reworked:
	Use podd style arrays in RVarDef.
	Get plane names (1pr, 2ta, 3ta, 4ta) from parameter file.
	Get block counts from parameters instead of hardwiring.
	Rename histogram names to be A,B,C,D 1-13, instead of 1-52

of hardwiring them.

  It has not been check that we are getting a good start time yet.
  Drift time and distance added to tree
  Change DC plane names from 1, 2, 3, ... to 1x1, 1y1, ...
    This is so that the parameters holding the time to distance maps
       can be found.  (The parameters are e.g. hwc1x1fract)
    Need to find a way not to have to hard code these plane names.
       Either use wire angles (alpha) or some kind of parameter name mapping
  Changed output.def to match new plane names

    Define constants (e.g. plane counts) that are not defined in
    the ENGINE parameter files so that the detector classes
    can be more generic.
    Hodoscope and Aerogel now pick up plane and tube counts from this file

      Start adding to the drift chamber code.   Setup a class structure
      similar to what podd uses for the VDCs.  Raw hit class renamed
      to THcRawDCHit.  Signal hits are how THcDCHit, modeled after
      podd hits.  Add THcDCWire, and classes for time to distance conversion.
      Time to distnace conversion doesn't do anything yet.

      Find some improved DC parameter files so that min and max TDC limits
      are good for the run we are using.

      THcDriftChamberPlane asks ThcDriftChamber for many parameters.

    Register some more variables for the tree
    Clear fNelem of some arrays, not fNhits.
    Print method to print Aerogel pedestals.
    Make Pedestal analysis a bit more like the ENGINE.
    Initialize counters

Change shower plane names from 1z, 2z, 3z, 4z to 1pr, 2ta, 3ta, 4ta
  to match the names used in the parameters.
Fix up histogram names for new plane names.
Get rid of duplicate THaNonTrackingDetector::Init call.

detector parameters from the gHcParms (THcParmList).

pedestal event analysis at Decode, no cut needed on histograms need to assure
that events with HMS (evtype 1 and 3) get histogrammed.

Use cut file to determine what is a pedestal event.  Pedestal events
only proceed to Decode.
In Decode (Just THcHodoscope for now) loop through each plane and accumulate
pedestal data.  Calculate the pedestals at the first non-pedestal event.
Pedestals are just calculated, but nothing is done with them.

don't add to histograms.

to the (Hall C ENGINE style) map file being used.

Put map files in MAPS subdir.
Define correct map for run 50017 in test.database.
Add a script to display drift chamber hitmaps.
Fix make_cratemap.pl so that it makes an entry in db_cratemap.dat
  for all Fastbus slots.

use the run number to determine which parameter and map files to use.

be made either in output.def or by analyzing root tree.