Setup organization navigation

Overview

We will need to setup the navigation for the organization. We will be starting with the Directory page so we could just add that one to start.

Implementation plan

• Create a new organizations directory in lib/sidebars
• Create lib/sidebars/organizations/panel.rb
• Create lib/sidebars/organizations/menus/directory_menu.rb
• Create app/views/layouts/nav/sidebar/_organization.html.haml and render Sidebars::Organizations::Panel with shared/nav/sidebar shared partial
• Add Sidebars::Organizations::Panel to app/helpers/sidebars_helper.rb#L95