https://github.com/HJReachability/helperOC/blob/master/Intro%20to%20Reachability%20Code.pdf should be updated to say run `tutorial()` instead of `tutorial_test()` after naming change here https://github.com/HJReachability/helperOC/commit/d9ef7184d6cee62bf0d05955550d230eee329bca#diff-1288f7d3da9596112a3d143faf6c1847