refactor(http): add status() methods to RawStatus and ResponseHead
refactor(http): add status() methods to RawStatus and ResponseHead

This lets us convert RawStatus to StatusCode in Response without having to address the tuple index
directly.

tshepang/hyper,yazaddaruvala/hyper,yazaddaruvala/hyper,hyperium/hyper,nickgonzales/hyper,Twey/hyper,tshepang/hyper,hyperium/hyper,nickgonzales/hyper,Twey/hyper,nickgonzales/hyper,tshepang/hyper,Twey/hyper,hyperium/hyper