Fix compiler warnings: mark virtual functions with override; remove superfluously virtual functions
Fix compiler warnings: mark virtual functions with override; remove superfluously virtual functions

dariomangoni/chrono,rserban/chrono,projectchrono/chrono,projectchrono/chrono,rserban/chrono,Milad-Rakhsha/chrono,rserban/chrono,rserban/chrono,Milad-Rakhsha/chrono,dariomangoni/chrono,rserban/chrono,Milad-Rakhsha/chrono,projectchrono/chrono,rserban/chrono,Milad-Rakhsha/chrono,dariomangoni/chrono,Milad-Rakhsha/chrono,dariomangoni/chrono,Milad-Rakhsha/chrono,rserban/chrono,dariomangoni/chrono,projectchrono/chrono,projectchrono/chrono,projectchrono/chrono,dariomangoni/chrono