add feature 'follow by push'
* added 'category scanner' for new topics functional
Extension provide new feature: 'follow by push' in Laracasts discuss.
Extension check in background all threads, whitch you are subscribed for and if finds new updates -- push to you notifications.
* checks every 30 seconds
* autoremoved subscribeds, when no update 3 days
if you have any troubles, you can create new issue on project github. PR also welcomed