Misc: Use override and final C++11 keywords in a few places (mostly scripts)

OVERRIDE and FINAL are TC macros (expand to nothing if compiler does not  support C++11)

src/server/scripts/Commands/cs_debug.cpp

@@ -40,7 +40,7 @@ class debug_commandscript : public CommandScript
 public:
     debug_commandscript() : CommandScript("debug_commandscript") { }
 
-    ChatCommand* GetCommands() const
+    ChatCommand* GetCommands() const OVERRIDE
     {
         static ChatCommand debugPlayCommandTable[] =
         {