WIP: Return array/object instead string when possible

[Jerome1337]

Fixes #83

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Tests

• Run the tests tests with npm test or yarn test

Returns object or array instead flatted object. Objects are not flatted anymore, plain JavaScript object is returned.

Strings {variable} are still working, even in nested objects.

• Write some docs

[kaisermann]

Hey, 👋 Thanks for starting your contribution. However, as this is a draft for quite a while, I'm closing this in favor of #105.