Feature: Introduce Super Admins (#705)

* Feature: Introduce Super Admins

- added new devise model for super user
- added administrate gem
- sample dashboards for users and accounts

Co-authored-by: Pranav Raj Sreepuram <pranavrajs@gmail.com>

spec/controllers/super_admin/super_admins_controller_spec.rb

@@ -0,0 +1,24 @@
+require 'rails_helper'
+
+RSpec.describe 'Super Admin super admins API', type: :request do
+  let(:super_admin) { create(:super_admin) }
+
+  describe 'GET /super_admin/users' do
+    context 'when it is an unauthenticated super admin' do
+      it 'returns unauthorized' do
+        get '/super_admin/super_admins'
+        expect(response).to have_http_status(:redirect)
+      end
+    end
+
+    context 'when it is an authenticated super admin' do
+      it 'shows the list of super admins' do
+        sign_in super_admin
+        get '/super_admin/super_admins'
+        expect(response).to have_http_status(:success)
+        expect(response.body).to include('New super admin')
+        expect(response.body).to include(super_admin.email)
+      end
+    end
+  end
+end