* Add handleShutdown Test of MongoStorageAdapter.
* Add `handleShutdown` function in PostgresStorageAdapter, with it's test.
* Replace the _pgp to _client
* Use `adapter._client.$pool.ending` to ckeck is ending
* Add `handleShutdown()` in ParseServer.spec.js
* Trigger
* Set Server to Default
* Added basic validation of publicServerURL
* Fixed up 'verifyServerUrl' and added tests
* Use Parse.serverURL instead, general cleanup.
* Test server port moved to 13376
* Removed reconfigureServer calls with simple changing of Parse.serverURL
* changed var to const
* Disabled automatic serverURL verification during testing, moved verification call into app.on('mount') callback, removed setTimeout from verification.
