Feature-packs should optionally depend on jdk-unsupported and sun.jdk

Currently our feature-packs depend on both "sun.jdk" and "jdk.unsupported" in an inconsistent manner. For the latest versions of Wildfly, we need to use the latter, whilst for older ones we need to use the former. Therefore, for all modules that require access to unsupported classes, we must provide an optional dependency on both of the above modules.