A few compiling issues

I had a few issues compiling, and these commits fix them. I'm not sure if perhaps there was an issue on my end with GEANT versions w.r.t. -Werror (I used 4.9.6.p03), so maybe someone can confirm.
Why remove this? `RTypes.h` defines the ROOT type(def)s like `Int_t`, `Float_t`, etc., which are used in this file.