Protostream should be used as the default marshaller for user types unless a user explicitly provides a custom marshaller via SerializationConfiguration.marshaller.

This requires that all of our testsuite is also updated to provide protostream pojos and that the `infinispan-jboss-marshalling` dependency is removed from all possible sub-modules. Most notably:

• core
• query
• server
• client

This will require various integration tests to also be updated to reflect the new behaviour, as the APPLICATION_JBOSS_MARSHALLING media type will not be available to the client/server by default.

In order for a user to utilise jboss-marshalling on the client side, it's necessary for the `infinispan-jboss-marshalling` jar to be added to the classpath. Furthermore, if APPLICATION_OBJECT storage is desired on the server and jboss-marshalling is utilised on the client, it's also necessary for the dependency to be added to the server. In order to verify that this functionality works as expected, it's necessary for a `integrationtests/jboss-marshalling` sub-module to be created in order to test these scenarios.