Create enum entries for deserialized enum classes
Regenerate built-ins serialized data

After changes to protobuf binary format
Simplify class object naming madness

- get rid of DescriptorNamer, always use descriptor.getName() instead
- delete AbstractClassResolver.getClassObjectName(), always use
  "<class-object-for-...>", except for the case of built-ins serialization
  (class object names should be replaced by "object" when writing files with
  serialized data for built-ins)
- delete NestedClassResolver.resolveClassObject(), always use the other method
  of this class instead