Update parse SDK to 2.0.0 (#4925)

* WIP: Integrate JS SDK v2

- Removes backbone style callbacks
- Use Promise instead of Parse.Promise

* Fixes ParseObject and ParseRelation

* Updates Parse.Query with promises

* Alls tests should pass

* Ensure a fresh user is used for each test

* Use REST implementation to avoid side effects for username/email duplicates

* Uses js sdk v2

spec/index.spec.js

@@ -292,7 +292,7 @@ describe('server', () => {
               }).then((obj) => {
                 expect(obj.id).toEqual(objId);
                 server.close(done);
-              }).fail(() => {
+              }).catch(() => {
                 server.close(done);
               })
             });