PIM-2672 : add an optional related-entity parameter in view tree
requests
PIM-2672 : pass relatedEntity variable from category controller to twig templates
PIM-2672 : use relatedEntity variable in twig templates related to tree
rendering and update the related twig extension
PIM-2672 : fix CS
PIM-2672 : use the related entity in the category extension
Merge branch 'master' into feature/tree_with_other_entity
Merge pull request #1166 from akeneo/feature/tree_with_other_entity

PIM-2672 : add an optional related-entity parameter in view tree requests