Make JPetParamGetter base class' destructor virtual
Make JPetParamGetter base class' destructor virtual


Former-commit-id: 1efe0c32086271cf0bf3074c171b0a4bdb4a6553
JPETTomography/j-pet-framework,JPETTomography/j-pet-framework,alexkernphysiker/j-pet-framework,JPETTomography/j-pet-framework,wkrzemien/j-pet-framework,alexkernphysiker/j-pet-framework,wkrzemien/j-pet-framework,alexkernphysiker/j-pet-framework,wkrzemien/j-pet-framework,wkrzemien/j-pet-framework,alexkernphysiker/j-pet-framework,alexkernphysiker/j-pet-framework,wkrzemien/j-pet-framework