ProcessObserverMethod is different btw spec and API

As stated in CDI-88 the spec and API is different for ProcessObserverMethod.

In the spec there is a method

public AnnotatedParameter<T> getAnnotatedEventParameter();

but in the API there is

AnnotatedMethod<X> getAnnotatedMethod();

which imo makes much more sense anyway.

Thus we should amend the spec wording finally.