* The ThreadLocal Serialization.currentTransportInformation is used for serializing local
actor refs, but it's also useful when a serializer library e.g. custom serializer/deserializer
in Jackson need access to the current ActorSystem.
* We set this in a rather ad-hoc way from remoting and in some persistence plugins, but it's only
set for serialization and not deserialization, and it's easy for Persistence plugins or other
libraries to forget this when using Akka serialization directly.
* This change is automatically setting the info when using the ordinary serialize and deserialize
methods.
* It's also set when LocalActorRefProvider, which wasn't always the case previously.
* Keep a cached instance of Serialization.Information in the provider to avoid
creating new instances all the time.
* Added optional Persistence TCK tests to verify that the plugin is setting this
if it's using some custom calls to the serializer.
e6633f17fa