Add UI dashboard support for Bull queues

[humphd]

We're using Bull to manage our work queues, so let's also add a UI so we can see what's happening. https://github.com/vcapretz/bull-board will give us the ability to add a route to a web server to show what's happening in our queues:

Eventually this should be behind an admin login, but for now, we can expose it. It will probably make debugging easier too.

[varshannagarajan]

I would like to look into setting this up. I could try and just start on setting this up while someone is working on issue #63 if that makes sense. Then add it to that server.

[neilong31]

@varshannagarajan I'd like to work on this with you if that's okay?

[varshannagarajan]

Yeah absolutely!

[humphd]

The Express web server just landed on master (thanks @miggs125)! You can do this easily now. Take a look at the code in src/server to hook your route into it.

[humphd]

Fixed in #200