- Many warnings in shadowing variables, eg.
  ConfigurationManager.hh

- data members not initialized - DetectorConstruction.hh

- virtual functions - DetectorConstruction.hh
   - declare with override, virtual keyword can be then ommitted

- deleted functions - DetectorConstruction.hh
   - Prefer deleted functions to private undefined ones.

- Using auto - example in CalorimiterSD.cc

- range based for loop (C++11) + structured bindings (C++17)
    PrimaryGeneratorAction
    ColorReader

- No need to call class member functions via this->
    CalorimeterHit.cc

- No need to test pointer before calling delete:
    - if pointer is 0, delete call has no effect
    InteractionSD.cc

- static PrimaryGeneratorAction::getInstance() 
    not needed, if used, should be thread local