* rulesets/TransientProperty.h, rulesets/MultiHandlerProperty.h,
rulesets/MultiHandlerProperty.cpp, rulesets/MindProperty.h,
rulesets/InternalProperties.h, rulesets/HandlerProperty.h,
rulesets/HandlerProperty.cpp: Switch a bunch of pretty simple
property classes over to using Propery<> rather than
DynamicProperty<>.
* rulesets/BBoxProperty.cpp, rulesets/BBoxProperty.h: A new property
to make BBOX optional and more dynamic.
* rulesets/MultiHandlerProperty.cpp, rulesets/MultiHandlerProperty.h,
rulesets/MultiHandlerProperty_impl.h: A new property for those
generic properties that need many handlers.
