Refactor exports controller (#1567)

* Add basic coverage for settings/exports controller

* Remove unused @account variable from settings/exports controller

* Add coverage for download export actions

* Remove deprecated `render :text` in favor of `send_data` for csv downloads

* Add model to handle exports

* Use Export class in settings/exports controller

* Simplify settings/exports controller methods

* Move settings/export to more restful routes

spec/controllers/settings/exports_controller_spec.rb

@@ -0,0 +1,14 @@
+require 'rails_helper'
+
+describe Settings::ExportsController do
+  before do
+    sign_in Fabricate(:user), scope: :user
+  end
+
+  describe 'GET #show' do
+    it 'returns http success' do
+      get :show
+      expect(response).to have_http_status(:success)
+    end
+  end
+end