public void setContext(Object context) {
        this.context = context;
    }
Sets a new context for this routable. Please note that the context is <u>not</u> something that is passed along a
message, it is simply a user context for the handler currently manipulating a message. When the corresponding
reply reaches the registered reply handler, its content will be the same as that of the outgoing message. More
technically, this context is contained in the callstack of a routable.
messagebus/src/main/java/com/yahoo/messagebus/Routable.java