Heroku deployment
I keep getting this error in heroic deployment:

```
 > node-sass@4.5.3 postinstall /tmp/build_4dc4038e016d7efeea98cb941984f357/node_modules/node-sass
remote:        > node scripts/build.js
remote:
remote:        module.js:472
remote:        throw err;
remote:        ^
remote:
remote:        Error: Cannot find module 'lru-cache'
```