StGammaJetMaker read jet, skim, and EemcDst trees and select/write gamma-jet tree.

• StGammaJetMaker.h / StGammaJetMaker.cxx
   
• StRoot/StGammaJetMaker/StGammaJetMaker subdirectory has:
  
  CheckNeighbors.h - simple code to check if the towers are adjacent
  Constants.h - list of constant used by the StGammaJetMaker
  getNextEemcTowerId.h - get the id of the adjacent tower
  Make.h - pice of code which reads the trees and fills the EemcDst event