Bump require-dir to 0.3.2

[lazerwalker]

Hi! Thanks so much for this project — looking forward to poking at it as an example!

Node v8 introduced some breaking changes that break versions of require-dir prior to 0.3.2. On my local dev machine, which runs Node 8, a clean clone and npm install of this repo pulled down an older version of request-dir that crashes on run.

This just bumps the package.json to use a version of require-dir that has the node 8 fix. The more proper solution would be to introduce a lockfile of some sort (whether a yarnfile.lock or package-lock.json), but seeing as this isn't my project I don't want to pick a side on yarn vs npm for you :P.

[ryangardner]

I can confirm that this fixed #42 for me by bumping this version up.

For people using node 8 (which anyone following the instructions and doing a brew install node will have at this point) - this fix is necessary.

[chrmitchell]

this fixed issue #42 (and issue #54) for me as well.

[lazerwalker]

@rjamison any chance of getting this merged? It's a very small non-code change that means the project is actually usable in a modern node stack.

[samdobson]

I'm not sure this repo is being maintained any more. I'm maintaining an updated version with this fix included at samdobson/interactive-adventure-game-tool