Add ability to set the SerializationContext in the function configuration

Add ability to set the SerializationContext in the function configuration.

exemple :

    wa72_json_rpc:
        functions:
            myfunction1:
                service: "mybundle.servicename"
                method: "methodofservice"
                jms_serialization_context:
                    group: "my_group"
                    version: "1"
                    max_depth_checks: true
            anotherfunction:
                service: "bundlename.foo"
                method: "bar"
                jms_serialization_context:
                    version: "1"
                    max_depth_checks: false
ref : PR #3 & #10