Specify behavior for sealed types

Sealed types are valid bean types, but they are unproxyable.

This commit only makes explicit what already implicitly follows from
the existing CDI specification and updates in the Java / JVM specifications.

spec/src/main/asciidoc/core/definition.asciidoc

@@ -81,7 +81,7 @@ The bean types of a bean are used by the rules of typesafe resolution defined in
 
 Almost any Java type may be a bean type of a bean:
 
-* A bean type may be an interface, a concrete class or an abstract class, and may be declared final or have final methods.
+* A bean type may be an interface, a concrete class or an abstract class, may be declared sealed or non-sealed or final, and may have final methods.
 * A bean type may be a parameterized type with actual type parameters and type variables.
 * A bean type may be an array type.
 Two array types are considered identical only if the element type is identical.

spec/src/main/asciidoc/core/implementation.asciidoc

@@ -662,6 +662,7 @@ Certain legal bean types cannot be proxied by the container:
 * classes which don't have a non-private constructor with no parameters,
 * classes which are declared final,
 * classes which have non-static, final methods with public, protected or default visibility,
+* sealed classes and sealed interfaces,
 * primitive types,
 * and array types.