adds spec for error messages on registration signup [#99]

spec/features/organizations_spec.rb

@@ -22,6 +22,14 @@ feature 'Organizations' do
     expect(user.organization).to_not be_verified
   end
 
+  scenario 'Errors on create' do
+    visit new_organization_registration_path
+
+    click_button 'Sign up'
+
+    expect(page).to have_content error_message
+  end
+
   scenario 'Shared links' do
     visit new_user_registration_path
     expect(page).to have_link "Sign up as an organization"