draft implementation of moving the object with the mouse

In the ScenarioEditor the following code was added.

```
//--------------------------------------------------------
void ScenarioEditor::mouseDragged(ofMouseEventArgs &args){
    ofVec3f newPos;
    if (selectedObject != NULL){
        
        newPos = selectedObject->position;
        newPos.x = newPos.x + (args.x/1000);
        newPos.y = newPos.y + (args.y/1000);
        selectedObject -> position = newPos;
        selectedObject -> setPosition(newPos);
    }
}
```

For the moment the new position is not calculated well because the object moves only in one direction.
The position is changed by calling SimpleObject::SetPosition that created a new rigid body.
We should see what is the impact of this
```
void Hammer::setPosition(ofVec3f position){

    btTransform transform;
    btRigidBody* rigidBody = body.getRigidBody();
    rigidBody->getMotionState()->getWorldTransform( transform );
    btVector3 origin;
    origin.setX(position.x);
    origin.setY(position.y);
    origin.setZ(position.z);
    transform.setOrigin(origin);
    rigidBody->getMotionState()->setWorldTransform( transform );
    
}
```