Fetcher as a module

* I was finding the tests for providers remote attributes to be rather pointless especially If I'm stubbing their private fetch method and having it return a mock.
* All the video providers memomize the result returned from fetch independently. The request hash within fetcher was an unnecessary complexity
* I still think the behaviour between a provider and fetcher isn't perfect but at least i'm now testing that Fetcher was actually at least called and not stubbing functions / methods within providers themselves.
Merge branch 'master' of github.com:karlentwistle/lumiere