Upgrade react-scripts

[rmccue]

We're a bit behind here, so we should update, which should give us a bunch of fun stuff from newer react-scripts/webpack/etc.

[pdewouters]

To note that 2.* introduced chunked assets to the build process output. This makes it a bit tricky if the project expects to enqueue a singlebundle.js file.

[kadamwhite]

We can disable code-splitting if needed (see this GH thread) but I'll look into what might be needed to support it out of the box.

[josephfusco]

Would love to help make this happen. Is there any work already being done on this?

[kadamwhite]

I began a branch to work on this upgrade, but ran into issues with the code-splitting. If you have interest in having a go, @josephfusco, please be my guest!

[josephfusco]

Just wanted to say I unfortunately have not had much time to work on this. If anyone else would like to work on this they are more than welcome to!

I was able disable code splitting using this solution however I am not sure that would suffice for this project. FYI there has also been some talk on restructuring asset-manifest.json generated from CRA2.

[roborourke]

Hey all, I have a PR that works here: #42

No need to disable code-splitting :)