* Interface Taxonomy:
* Group I: 
*       Port *, Component *, Services *.
* Group II:
*       ComponentID, ConnectionID, TypeMap, ConnectionEvent,
*       ComponentClassDescription.
* Group III:
*       Exception class and derivatives.
*
*
* Group I characteristics:
*
* These are the several fundamental interfaces which must (and can)
* remain purely virtual (no standard ref-counting base object in c++)
* so that any framework or component can implement them cleanly 
* and mutually compatibly. These are handled as pointers to interfaces
* and have a well-delimited lifecycle within the component framework
* definition (add/remove, get/release, create/destroy, and
* setServices(p)/setServices(null)). All known c++ ref-counting schemes
* place to great a burden (startup cost) on scientific programmers.
* Maintaining these interfaces as pure virtual interfaces allows the natural idiom
* of C++ interfaces (dynamic_cast) to be applied. It also allows them
* to be passed through babel components as opaque items without
* the gymnastics that passing a boost::shared_ptr through babel does.
* All specific ports derive from Port, thus everything above applies 
* to all component ports.
*
*
* Group II characteristics:
*
* These are objects which pass through several Ports or interfaces,
* though all are ultimately created by the framework. Components
* might choose to hold onto one of these, so a shared-pointer/ref-count
* mechanism is necessary. Boost provides such a mechanism.
* The raw, still pure virtual interfaces in this group are named
* YYY_Interface and the component writer simply references
* YYY_ptr as objects, since YYY is from
* typedef ::boost::shared_ptr< YYY_Interface > YYY_ptr;.
*
*
* Group III characteristics:
*
* The typical C++ pattern for exceptions is to throw an
* object that is on the stack and catch it as a reference
* to the object. E.g. 'throw Exception("message");' when an error
* occurs and at a higher scope 'try {...} catch (Exception &e) { ... }'.
* As such, we must all agree to use a common, simple exception
* such as the one fully implemented in this header and derived
* from ::std::exception and the CCAException specification of cca.sidl.
*