Upgrade hapi to 16.6.0

[jseppi]

and all its submodules, including content, to fix a regex dos issue (ref #53)

[jseppi]

Interestingly, I couldn't just do yarn upgrade hapi to get the upgraded content module, which is actually a sub-sub-depedency. It's immediate parent is subtext. subtext just specifies content version 3.x.x and we needed 3.0.6 specifically.

To get the newest version, I had to do yarn remove hapi && yarn add hapi, which removed and re-added the entire hapi dependency tree.

There's an issue about this behavior over at yarn: yarnpkg/yarn#2394

[wslack]

Let's go ahead and push this to prod @jseppi.