Exporting a corpus works, as it also exports its children, but for
example the docs and terms nodes do not have any associated content.
This is because those are stored in separate DB tables, and we need
to find a way to export those as well.

It typechecks but it exchange only a very simple string and
it prints it.

This adds a new randomly-generated pair of (PublicKey, PrivateKey) to be
later used to send messages between instances.

It also:

* Returns a remote transfer pub key inside an AuthResponse
* Adds pubKey roundtrip test

[graphql] fix droping field prefixes

See merge request !379

Upgrade 'haskell-bee' version, also bump up versions of some packages

See merge request !377

Resolve "Fix test build warnings"

See merge request !376

Also, add -Werror to tests so that no warnings in tests are reported anymore.

Switch to OpenAPI3 from Swagger2, to use proper Bearer token

Closes #427

See merge request !369

This commit adds three major tags to the swagger UI:

* Gargantext (like before): this spells out all the endpoints;
* Private operations: lists private backend ops;
* Public  operations: lists public backend ops.

More can be added, but the machinery used here should serve as a
blueprint.

OpenAPI3 will allow us to properly pass the Bearer Auth to the servant
swagger UI.

I fixed those warnings that were easy to fix: redundant imports, unused
variables, etc. (I might have missed some though)

The warnings I deliberately left for now are:
* In `Test.API.UpdateList`: Incomplete pattern matching (we would need
  to think a bit about error handling to fix this)
* In `Test.Utils`: `traceShowId` remains in code (we would need to think
  a bit about proper logging to fix this)

Resolve "Refactor `Gargantext.Database.Prelude`"

Closes #421

See merge request !372