Revert "Upgrade React 16 - FINAL"

[sethbergman]

Reverts #549

[sethbergman]

https://reactjs.org/blog/2017/07/26/error-handling-in-react-16.html

[sethbergman]

https://operation-code.slack.com/files/U42VC995G/F7BQMMREY/webpack-output_js.js

[sethbergman]

[sethbergman]

Access-Control-Allow-Headers:X-Sentry-Auth, X-Requested-With, Origin, Accept, Content-Type, Authentication
Access-Control-Allow-Methods:GET, POST, HEAD, OPTIONS
Access-Control-Allow-Origin:https://operationcode.org
Access-Control-Expose-Headers:X-Sentry-Error, Retry-After
Cache-Control:max-age=0
Connection:keep-alive
Content-Language:en
Content-Length:41
Content-Type:application/json
Date:Mon, 02 Oct 2017 07:19:58 GMT
Expires:Mon, 02 Oct 2017 07:19:58 GMT
Last-Modified:Mon, 02 Oct 2017 07:19:58 GMT
Server:nginx
Strict-Transport-Security:max-age=31536000; includeSubDomains; preload
Vary:Accept-Language, Cookie
X-Content-Type-Options:nosniff
X-Frame-Options:deny
X-Served-By:web-e3e9e887
X-XSS-Protection:1; mode=block

[sethbergman]

https://operation-code.slack.com/archives/C1J6NPCSV/p1506925416000066