Improve AnnotationLiteral for empty annotations

Annotation hashCode() and equals() operations are fairly expensive as they always invoke getDeclaredMethods() even if there are no such. And getDeclaredMethods involves the SecurityManager + wrapper classes + Exception handling + + +
That's horrible expensive.

In OWB I improved this by introducing an own base class for dynamic annotations which do not have any members:
https://github.com/apache/openwebbeans/blob/trunk/webbeans-impl/src/main/java/org/apache/webbeans/annotation/EmptyAnnotationLiteral.java

The method returns a hardcoded String for toString(), returns hardcoded 0 as hashCode and the equals() method invokes the equals on the annotation type.

We might support this improvements directly in the AnnotationLiteral class or introduce a similar 2nd class especially for empty annotations?