Update Notification Refactor (#511)

* Replaced profile links to anchors so we can open in new tab if we like

* Refactored how update checking works. We now explicitly check and send back on the same API. We have a weekly job that will push an update to the user.

* Implemented a changelog tab

* Ported over a GA fix for using ' in PR bodies.

* Don't check cert for Github

API/Interfaces/ITaskScheduler.cs

@@ -15,6 +15,5 @@
         void RefreshSeriesMetadata(int libraryId, int seriesId);
         void ScanSeries(int libraryId, int seriesId, bool forceUpdate = false);
         void CancelStatsTasks();
-        void CheckForUpdate();
     }
 }