Clearing all subscriptions should close out the connection

[dhinklexo]

Context

• node version: 8
• bunnybus version: latest
• environment (node, browser): node

What are you trying to achieve or the steps to reproduce ?

Calling bunnyBus.subscriptions.clearAll(); should close all connections. Currently the only way to stop the dangling connection is to call the internal methods. This dangling connection will cause test runners to hang and other weird/undesirable behavior.

[lamchakchan]

can you provide a simple example around this?

[dhinklexo]

   const bunnyBus = new BunnyBus(this.options.bunnybus);

    server.ext('onPreStop', function() {
        bunnyBus.subscriptions.clearAll();

        //unless below is uncommented, the rabbit instance will keep a dangling connection
        //return bunnyBus._closeConnection();
    });

    return bunnyBus.subscribe('hapi-reviews-reminder', {
        'reviews.webhook':...