begin of reverting hist structure.
Now it is Bin-BGSub-ScaCor. Will be faster by default if ScaCor-BGSub-Bin.
GH1 is doing only binning now.
simplify virtualisation in GLinkedHist.
Renamed GH1 in GHistTaggerBinning.
Added default constructor to GHistLinked.
Added member function Link and Unlink to GHistLinked.
Added default constructor and SetBins to GHistTaggerBinning.
Removed copy constructor in GHists to avoid naming problems with root.
Including only pi0-example in CMakeList
PPhysics library now based off GH1 histograms
Updated PPi0 example class - using GH1
Removing un-needed GH1example
Removing un-needed PEtaexample
Removing un-needed MyGoAT
Removing un-needed GKinFitter classes
Changes to meson reconstruction

Possibility for charged pions to be included in pi0 reconstruction
is now rejected. Still included into eta and eta' reconstruction.
Pi0 reconstruction only from photons and rootinos
fixing small bug in last commit
Changes to meson reconstruction

Rejection of Ek == 0 particles from meson reconstruction is included.
This is needed as the CentralApparatus class will create particle tracks
using the PID and MWPC if possible. In this case, the Ek is 0 as no
calorimeter information is available. If these particles are allowed
to be included in the meson reconstruction, they are just included
as an additional daughter (without actually changing the lorentz vector).
For this reason, they shouldn't be included.
Fixing meson recon. check
Found error in GTreeMeson - fixed
Fixing another small error in GTreeMeson