Fixes multiple complete and uncomplete for todos and daily (Fixes #8669) (#8971)

* Fixed bug that allows users to complete todo and daily multiple times

* Added tests

* Fix syntax

* Fix existing tests that rely on multiple complete or uncomplete

* Undoes removal of website/client/README.md

* Change sessionOutdated string to reflect separate client needs

* Fix should update history test by changing lastCron

test/api/v3/integration/tasks/challenges/POST-tasks_challenges_challengeId_tasks_id_score_direction.test.js

@@ -82,6 +82,13 @@ describe('POST /tasks/:id/score/:direction', () => {
     });
 
     it('should update the history', async () => {
+      let newCron = new Date(2015, 11, 20);
+
+      await user.post('/debug/set-cron', {
+        lastCron: newCron,
+      });
+
+      await user.post('/cron');
       await user.post(`/tasks/${usersChallengeTaskId}/score/up`);
 
       let tasks = await user.get(`/tasks/challenge/${challenge._id}`);