Update to hapi 3.x

As with spumko/yar#28, this suggests updating travelogue to work with Hapi 3.x.

Tests pass, but coverage is not 100% (same issue on master for me):
```
$ make test-cov
  ..............................

 30 tests complete (200 ms)

 No global variable leaks detected.

Coverage: 99.59%

lib/index.js missing coverage on line(s): 202
Code coverage below threshold: 99.59 < 100
make: *** [test-cov] Error 1
```