#18 Using HTTP HEAD instead of GET

Addressing #18 

Also abstracted the request logic to allow for removing the ``HttpRequest`` lib in the future. 

Could expose this to client to allow for custom requests.
so you can make this change at your leisure @ouchadam as my fix won't be merged into our project today. I'll start looking at your other PR and also get mine ready (Merlin) for tomorrow as I expect it'll need changes throughout the day :tongue: