Revise EventTypeAssignabilityRules

In EventTypeAssignabilityRules, method isAssignableFrom(Type type1, Type[] types2) seems to be incorrect - it is called from isTypeInsideBounds() with expectation that type1 has to assignableFrom each Type from types2, not from at least one as is the case.

Other such incorrect methods are:

• isAssignableFrom(Type type1, Set<? extends Type> types2)
• isAssignableFrom(Type[] types1, Type type2)