DATACMNS-400 - PersistentProperty now exposes findAnnotation(…).

Pulled up the method declaration from AnnotationBasedProperty as it's useful to be able to inspect a property for annotations being configured on it independently from whether the persistent mapping of it has been defined via annotations or not.

Expose isAnnotationPresent(…) as well to ease quick checks for an annotation.
DATACMNS-401 - Some cleanups regarding generics and deprecations.

Suppress deprecation warnings for GenericTypeResolver for now. Added Simple(Property|Association)Handler to ease working with untyped PersistentProperty instances without having to fall back to raw types. Polished Sonargraph architecture description.