add Geant namespace

src/HEP/Geant/DetectorConstruction.hh

@@ -9,6 +9,7 @@ class G4VPhysicalVolume;
 class G4LogicalVolume;
 
 namespace uLib {
+namespace Geant {
 
 class DetectorConstruction : public G4VUserDetectorConstruction {
 public:
@@ -20,6 +21,7 @@ public:
   virtual void ConstructSDandField();
 };
 
+} // namespace Geant
 } // namespace uLib
 
 #endif