refactor(frontend api interactions)

* Complete redesign of the api actions / reducers,
* Now makes use of Axios,
* No more black magic,
* Doc updated,

BREAKING: All `...Specific` reducers results are no under `...One` and `readSpecific` moved to `readOne`

Also,
* Fixed bug regarding opposite user_can_moderate value returned by backend

Fixes #98
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merge request