Concrete Classes and Descendent Subs

[milt]

• Make trigger dispatch matching hierarchy-aware, in that it will fire on a subclass of a configured class (so a SimEntity ObjectUpdate fires when we get a Rabbit update for instance)
• Enable subscription plan to get descendant information
• Subscribe to child classes and superclass in reverse topo + deterministic lex ordering. The reverse topo order leads to RTI giving us the most specific class for a given object, the deterministic ordering keeps behavior predictable.
• Use fully-qualified class paths for compatibility with pitch