add support for user._tmp, disable user.filters since it is not used

test/api/v3/unit/models/user.test.js

@@ -0,0 +1,33 @@
+import { model as User } from '../../../../../website/src/models/user';
+
+describe('User Model', () => {
+  it('keeps user._tmp when calling .toJSON', () => {
+    let user = new User({
+      auth: {
+        local: {
+          username: 'username',
+          lowerCaseUsername: 'username',
+          email: 'email@email.email',
+          salt: 'salt',
+          hashed_password: 'hashed_password', // eslint-disable-line camelcase
+        },
+      },
+    });
+
+    user._tmp = {ok: true};
+    user._nonTmp = {ok: true};
+
+    expect(user._tmp).to.eql({ok: true});
+    expect(user._nonTmp).to.eql({ok: true});
+
+    let toObject = user.toObject();
+    let toJSON = user.toJSON();
+
+    expect(toObject).to.not.have.keys('_tmp');
+    expect(toObject).to.not.have.keys('_nonTmp');
+
+    expect(toJSON).to.have.any.key('_tmp');
+    expect(toJSON._tmp).to.eql({ok: true});
+    expect(toJSON).to.not.have.keys('_nonTmp');
+  });
+});