CD-18 Expose aws box url

@vasili-zolotov @d3ming 

This creates a link to the aws box that's created during ci. Right now it uses the users github icon as the button, but this can be changed later with a real icon. (I didn't want to take a stab at art)
Oh gotcha. So if I did something like parsing the output for the link I want to attach, wouldn't we need to standardize a pattern to search for? It's better from an engineering standpoint, but it seems like trading a feature dependency for a programmer responsibility dependency. But I can definitely see the advantage.