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

This reverts commit ff00345c

Also, use genericArbitrary in Instances, this simplifies things

Also, some import refactoring

This allows the frontend to correctly display a different icon in case a
node has been published with edits enabled or not.

This commit refactors a bit the internal of the
`Gargantext.Database.Query.Tree` module so that it removes a lot of
repetitive boilerplate and paves the way to more interesting features.

It also:

* Adds the `isUserNode` boolean query
* Adjust source and target in publishNode and unpublishNode
* Pass the currently-logged-in user to tree API functions

Also, removed some old job stuff

This allows us to collect a /history/ of computing times.

The tracking is not perfect yet, as it keeps storing only the latest
available compute time. Also, there seems to be some precision loss
between that is reported by `timeMeasured` and what gets stored in the
DB.

This was because WS connection wasn't closed properly.

This was because WS connection wasn't closed properly.