introduce organizations

app/controllers/admin/organizations_controller.rb

@@ -0,0 +1,19 @@
+module Admin
+  class OrganizationsController < Admin::BaseController
+    load_and_authorize_resource :organization
+
+    def index
+      @organizations = Organization.all
+    end
+
+    def destroy
+      if @organization.destroy
+        redirect_to admin_organizations_path,
+                    notice: 'Organization successfully destroyed'
+      else
+        redirect_to admin_organizations_path,
+                    error: 'Organization cannot be destroyed'
+      end
+    end
+  end
+end