Upgrade to Hapi 4.x

- Hoek is needed instead of hapi.utils
- I did run make test which passed and make test-cov
lib/index.js missing coverage on line(s): 69, 118, 122, 159, 194, 202
Code coverage below threshold: 96.53 < 100
- Would most likely need to upgrade to lab 3 but I got issues so I left it alone for now.