doc++: Use AnimableGroup3D instead of DrawableGroup3D for Animable3D.

Signed-off-by: Squareys <Squareys@googlemail.com>

src/Magnum/SceneGraph/Animable.h

@@ -78,7 +78,7 @@ typedef SceneGraph::Scene<SceneGraph::MatrixTransformation3D> Scene3D;
 
 class AnimableObject: public Object3D, SceneGraph::Animable3D {
     public:
-        AnimableObject(Object3D* parent = nullptr, SceneGraph::DrawableGroup3D* group = nullptr): Object3D{parent}, SceneGraph::Animable3D{*this, group} {
+        AnimableObject(Object3D* parent = nullptr, SceneGraph::AnimableGroup3D* group = nullptr): Object3D{parent}, SceneGraph::Animable3D{*this, group} {
             setDuration(10.0f);
             // ...
         }