Added b intheknow service and feed manager

Ive added a service to get the bintheknow feed from tumblr and a controller to manage the auto loading process.

added unit tests - integration tests to follow
It is probably an  architecture thing. But I'm confused of the inputs and outputs of this module. Is it a helper to extract functionality?

I think my confusion as when calling ```getFeed()``` I expect something to be returned.

If you want we can talk through this together.