* #314: Folder View: Split Horizontal / Vertical for folder or code views
* Sidebar UI/UX enhancement
* SASS members addition for left/right handling
* link handling hook interface

Merge branch '80-dev-frontend-errors' of ssh://gitlab.iscpif.fr:20022/gargantext/purescript-gargantext into dev

Merge branch '21-dev-automated-tests' of ssh://gitlab.iscpif.fr:20022/gargantext/purescript-gargantext into dev

Merge branch '21-dev-automated-tests' of ssh://gitlab.iscpif.fr:20022/gargantext/purescript-gargantext into dev

This was used only for testing frontend errors, commited by accident.

This way we can have a handle of the errors in the high-level
components. Before they were implicitly discarded.

* Issue #315

* Issue #309, feedbacks (2)

* Issue #293
* Issue #313
* Issue #316

The "nobody" route is the one which is working for now.

This reverts commit 9de1e1b5.

* #309: feedbacks