1) Add X,Y offsets parameter for each plane, instead of X,Y offset per chamber
2) ModifyTHcDriftChamber::CorrectHitTimes to work with SHMS chambers
3) Add GetReadoutSide method to THcDCHit class.

Main purpose is to calculate the DC efficiency per wire
using the track information of the golden track.


THcDC.h
-----------
1) add method EfficiciencyPerWire
2) Add variables fWire_hit_did and fWire_hit_should

THcDC.cxx
------------
1) fWire_hit_did and fWire_hit_should are fixed length arrays
   the size of NPlanes that in set in method Init
2) Add variables wireHitDid and wireHitShould to the tree
3) In method SetFocalPlaneBestTrack add call to EfficiencyPerWire method
4) added EfficiencyPerWire method which loops over the hits
    and compares the wire number for the hit to the the track
    position at the plane (convert back to wire number).
    Then fills fWire_hit_did with the wire number if
    equal to the wire position of the hit equals the track.
    Also does loop over all planes and fills fWire_hit_should
    with the wire number of the track in each plane.

THcDriftChamberPlane.h and cxx
---------------------
1) Added method CalcWireFromPos

Main purpose was to have option for per wire tzero offsets

Modified THcDriftChamberPlane.h
------------------------------
1) added fUsingTzeroPerWire as parameter flag to switch on per wire tzero offsets when parameter equals 1
2) fTzeroWire is array of tzero offsets for each wire in plane

Modified THcDriftChamberPlane.cxx
------------------------------
1) THcDriftChamberPlane::ReadDatabase
    a)set a default value of fUsingTzeroPerWire=0
    b)added to DBRequest list option to read in fUsingTzeroPerWire
    c) if fUsingTzeroPerWire=1 then separate DBRequest to read in fTzeroWire
   d) if fUsingTzeroPerWire=0 then all fTzeroWire=0

2) THcDriftChamberPlane::ProcessHits
------------------------------------
   a) Modify calcualation of drift time to subtract fTzeroWire
Double_t time = -StartTime- rawtdc*fNSperChan + fPlaneTimeZero - fTzeroWire[wireNum-1];

In tree they are called tnhit and trawhit.
Created two new variables for THcDriftChamber, fNthits and fN_True_RawHits.
In tree they are called tnhit and trawhit.
THcDC defined subdetector THcDriftChamber to have name Ch1 and Ch2 to do used in the tree.
THcDriftChamberPlane defined new method GetNRawhits to return fNRawhits for each plane.
Added member fNRawhits to THcDriftChamberPlane

  Uses ROOT matrix math instead of solve_four_by_four
  Nothing is done with found tracks yet.  Will need to stuff these into
     podd style tracks.  (Or a class inherited from podd style tracks.)
  Residuals not saved anywhere
  Single stub mode not yet implemented
  No printing out of trackfit results (hdebugtrackprint)

  THcDriftChamber::SpacePoint -> THcSpacePoint
  That way space points can be put in a TClonesArray and be made known
  to THcDC when stub information is added.

  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.

Pass a start time computed in THcHodoscope to THcDriftChamberPlane. A dummy value for the start time is used until the Hodoscope code actually computes the start time.

      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.

for older ROOT version wasn't working.

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

add simple code to register ADC and TDC hits into global
variables so that hit maps can be made.

Add ThcSignalHit class

Follow SRC model and make a scintillator plane class.