Implementation error in the RealtimePublisher doc example

[qleonardolp]

Hi there,

I've been studying the realtime_tools and the recently added RealtimePublisher. On the documentation example, the realtime publisher is declared as a shared_ptr class member, however in the on_configure() method the assignment is from std::make_unique:

https://github.com/ros-controls/realtime_tools/blob/master/realtime_tools/doc/realtime_publisher.rst

This doesn't lead to a compilation error, but is it ok? What could I be possibly missing?