aspnet
Make hub_connection always a shared_ptr
We talked about replacing the hub_connection_impl and making hub_connection contain all the logic. However, that would require including a lot of internal types in the public header and all sorts of ugliness.
This change would be great @BrennanConroy. We've recently got this client working in Unreal, but the current API makes it difficult to store a hub_connection in our classes (there's no default or copy constructors). We had to add a default constructor to the class in order to do so.
This change looks like the right kind of solution.
Looks like there's a move constructor available for hub_connection which allows us to use a shared pointer. But returning a shared pointer directly from the builder would be useful.
