Robotics Service Bus

Instead of having the user to define typedefs to the shared_ptrs used, we can do it internally.

E.g, instead of:

boost::shared_ptr<Publisher<string> StringPub;
StringPub p(new Publisher<string>(uri));

typedef boost::shared_ptr<string> StringPtr;
StringPtr s(new string("blub");

p->publish(s);

it should be possible to do the following using interal typedefs / factory funtions from within the Publisher:

Publisher<string>::Ptr p = Publisher<uri>::create(uri));
Publisher<string>::DataPtr s(new string("blub");

p->publish(s);

Using factory methods, we can also store a shared_ptr to self in the Publisher object.