+ geant4 files are kept in the include and src directories
   + one directory is created for each detector. This directory
     contains the associated headers and sources files
   + a script directory is created with some scripts allowing the
     conditional compilation

 * Add #ifdef statements in DetectorConstruction.cc file
   + this applies to each detector header

 * Move G4MultiFunctionnalDetector.hh header from Sharc.cc to 
   Sharc.hh

 - Put 2009-2013 copyright date
 - Change the place of the ifndef position to avoid multiple inclusion of comment line