Refactor Kakapo to not be json centric WIP

This is a draft PR to address #153, I want some feedback before proceeding with updating the documentation, README, tests The idea is that Router now doesn’t work anymore w/ Serializable objects and ResponseFieldsProvider is not anymore a special Serializable. Router now only accept ResponseFieldsProviders an object that provides: statusCode (Int) headerfields (dict) body (data)

Serializable became a ResponseFieldsProvider that by default has a status code == 200 and “Content-Type” == “application/json”. It should have been like that since ever, so we can use Kakapo with images, xml or whatever we want by creating new ResponseFieldsProvider

The change is a breaking change but not a big one for users of Kakapo (only objects that were confirming to ResponseFieldsProvider will be broken)

@zzarcon might be interesting also for Kakapo.js 🤷‍♂️

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+1 for this cos we need to use this to mock binary protobuf response. any updates?

@MP0w can you give us an update on this? is the project dead? 😢

hey @MP0w, same as @zzarcon, is the project dead ?