Reimplement the RDAP Json creation using Jsonables

Currently we try to reimplemnet the same behavior of the existing code as much
as possible.

We only fix issues that go against the RFC7483, but we don't yet update the
code to follow the latest (15feb19) RDAP Response Profile. That will require a
much bigger change especially for the test files, so it'll wait for a followup
CL.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=246948018

java/google/registry/rdap/AbstractJsonableObject.java

@@ -360,8 +360,6 @@ abstract class AbstractJsonableObject implements Jsonable {
    *
    * <p>If not empty - the resulting list is the allowed names. If the name ends with [], it means
    * the class is an element in a array with this name.
-   *
-   * <p>A name of "*" means this is allowed to merge.
    */
   static Optional<ImmutableSet<String>> getNameRestriction(Class<?> clazz) {
     // Find the first superclass that has an RestrictJsonNames annotation.