Fix stack balancing problems by refactoring execution calls

- Con::executef now uses a template
- All public execution functions now restore the console stack upon return
- Fixed bad parameters on some callbacks
- Reverts get*Arg behavior

Engine/source/T3D/pathCamera.h

@@ -93,7 +93,7 @@ private:
 public:
    DECLARE_CONOBJECT(PathCamera);
    
-   DECLARE_CALLBACK( void, onNode, (const char* node));
+   DECLARE_CALLBACK( void, onNode, (S32 node));
 
    PathCamera();
    ~PathCamera();