removes user_id column from User model to use idiomatic Rails automatic IDs

spec/support/user_fixture.rb

@@ -6,13 +6,16 @@ class UserFixture
   end
 
   def self.normal_user
-    password = "thi$ 1s cOmplExEr"
-    user = User.new(first_name: "Joe", last_name: "Schmoe",
-                    email: "joe@schmoe.com", password: password, password_confirmation: password)
-    def user.clear_password
-      "thi$ 1s cOmplExEr"
+    password = 'thi$ 1s cOmplExEr'
+    User.create!(first_name: 'Joe', last_name: 'Schmoe', email: 'joe@schmoe.com',
+                 password: password, password_confirmation: password).tap do |user|
+      def user.clear_password
+        'thi$ 1s cOmplExEr'
+      end
     end
-    user.save!
-    user
+  end
+
+  def self.admin_user
+    User.where(admin: true).first
   end
 end