Visual Test Shell for BACnet SVN

Re-designed the constructors for EPICS Objects to avoid endless duplication of code, adding handling for generic properties and also common properties (of fixed value).
Provided constructors for Characterstring, Integer, and DateTime Value objects.
Provided a generic default constructor for the other new Object types, until someone is willing to improve them.
Got fed up with some persistent warnings and so tamped them down with appropriate casts.