- controller golem15.user.organisations behind golem15.users.access_users
- list and form (name, slug preset from the name, description, avatar)
- members relation manager: link sets and unlink clears users.organisation_id
- deleting an organisation releases its members first
- Organisation gains Fillable, Rules, MorphName, AttachRelations, BeforeValidate
and the Members relation; models.Slugify
- navigation side item organisations
- TestAdminOrganisations, TestAdminOrganisationMembers, TestSlugify
