This commit introduces a new DB function called `isSharedWith`
that can be used to check for team/public/private nodes and their
shared resources.

This is a first stepping stone in avoiding bugs by having `UserId` and
`ContextId` being proper types, and not synonyms.

We also refactor things to have `AuthenticatedUser` carry the `UserId`.

Basically, Gargantext.Prelude exports all of Protolude now.

This commit partially undo the access policy checks for the
GraphQL endpoints, until we find a better story to correlate
the `user_id` we sometimes receive with the info from the
`AuthenticatedUser`.

This reverts commit a444cb30.

This reverts commit d04cf03b, reversing
changes made to e213a4bf.

Doesn't compile yet.

This is somewhere in Flow.hs in types for ConduitT () a m ()
where m monad is IO.