Allow directory to be passed as arg

[stevesloka]

It would be great to allow ir2proxy to take a directory as an arg to process a set of yaml objects instead of just a single yaml file.

[youngnick]

Agreed.

[youngnick]

However, I think I'd like to see how people actually use the tool so I can find out the best way to do this. I'm going to backlog this for now, until we can get some more user feedback.