Update code to export umd, cjs, esm etc

[weyert]

Why

In the past there has been tickets raised that the library isn't straight away usable with create-react-app and other projects. I have created a test app at: https://github.com/weyert/restful-react-demo

This PR contains a bunch of changes at first the contained in PR #211 but then also:

• Added new rollup-config specifically for the tools scripts named tools.rollup.config.js
• Changed the locations of the build artefacts:
  - Tools scripts end up in lib
  - Actually components end up in dist
• Expose size snapshots of the generated files
• Moved the test files to their dedicated folder named __tests__
• Added the necessary rollup-plugins

[seanlaff]

Psyched for this!

[fabien0102]

@weyert Sorry, you need to rebase this one, you have some commits from #211 in conflict

Something like this should do the job to avoid conflict resolution 😉:
git rebase --onto origin/master features/remove-operational-scripts features/just-use-rollup feature/

[fabien0102]

Why did you move everything inside a __tests__ folder? 🤔

[weyert]

No, really reason, mainly it was late and I was having a feeling it was leaking into the final builds. I am happy to revisit and move them back if you want.

[fabien0102]

I usually prefer my tests aside the component (otherwise people forget about these 😬), but I get the leaking part, I have the same locally 😕 (I was playing a bit with tsdx today, to give a try and see if need all this extra configuration)