It uses the (`const T &&... p_args`) forward reference, to avoid copying the
memory in case it's an rvalue, or pass a reference in case it's an lvalue.
This is an example:
```c++
PagedAllocator<btShapeBox> box_allocator;
btShapeBox* box = box_allocator.alloc( btVector3(1.0, 1.0, 1.0) );
```
AndreaCatania
c81cb64416