=act, ker, rem, doc #16330 deprecate akka.util.Crypt

* deprecate akka.util.Crypt
* fix documentation after deprecating
Merge pull request #16530 from skrauchenia/fix/16330-akka-util-Crypt-deprecate-skrauchenia

=act #16330 deprecating akka.util.Crypt
=rem #16428 optimize protobuf serializer