A0: Improve styled components debugging

[jalooc]

This is my small initiative to improve styled components debugging: the import change from styled-components to styled-components/macro turns on enhanced debugging tools *, which, among others, add readable component names to the otherwise inhuman class hashes:

before -> after

I turned it on locally to make familiarizing with the repo easier; figured I'd make a PR since it's an overall very useful feature.

Note: Fear not the number of changed files - almost all of them are the same, tiny change.

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* Normally we'd use a babel plugin for that and thus not have to update the import statements, but since CRA does not allow custom babel config, I had to fall back to using the macro.

[jalooc]

Turning off the readable names on production - I guess we better not disclose internal, dev details so openly.

[Kocik]

Looks good! I'd not it as a potential change to merge to it up to upstream? We could talk to Ross, the original author when the time comes.

[jalooc]

@Kocik Yes, it's a definite candidate for the upstream. Quite significantly improves DOM/components debugging experience using the tools they already have, for pretty much zero cost. Unless they have already solved the problems in a different way: using CRA-rewire (which I did not peak because it's more of a hack).

[jalooc]

FYI I'll hold on with merging this until the merge with upstream. This PR is neither breaking, nor intrusive, but involves many files so might make the big merge tad harder - something to consider when we're closer to the that date.